diff --git a/script/cibuild b/script/cibuild
index 794441cc..64016bb7 100755
--- a/script/cibuild
+++ b/script/cibuild
@@ -48,6 +48,8 @@ python3 spec_tests.py --no-normalize --spec ../../../src/tests/fixtures/wikilink
   || failed=1
 python3 spec_tests.py --no-normalize --spec ../../../src/tests/fixtures/wikilinks_title_before_pipe.md "$PROGRAM_ARG -e wikilinks-title-before-pipe" \
   || failed=1
+python3 spec_tests.py --no-normalize --spec ../../../src/tests/fixtures/description_lists.md "$PROGRAM_ARG -e description-lists" \
+  || failed=1
 
 python3 spec_tests.py --no-normalize --spec regression.txt "$PROGRAM_ARG" \
 	|| failed=1
diff --git a/src/html.rs b/src/html.rs
index e8ac2303..b4142fd3 100644
--- a/src/html.rs
+++ b/src/html.rs
@@ -512,7 +512,7 @@ impl<'o, 'c: 'o> HtmlFormatter<'o, 'c> {
                     self.cr()?;
                     self.output.write_all(b"<dl")?;
                     self.render_sourcepos(node)?;
-                    self.output.write_all(b">")?;
+                    self.output.write_all(b">\n")?;
                 } else {
                     self.output.write_all(b"</dl>\n")?;
                 }
@@ -696,14 +696,15 @@ impl<'o, 'c: 'o> HtmlFormatter<'o, 'c> {
                     .map(|n| n.data.borrow().value.clone())
                 {
                     Some(NodeValue::List(nl)) => nl.tight,
+                    Some(NodeValue::DescriptionItem(nd)) => nd.tight,
                     _ => false,
                 };
 
-                let tight = tight
-                    || matches!(
-                        node.parent().map(|n| n.data.borrow().value.clone()),
-                        Some(NodeValue::DescriptionTerm)
-                    );
+                // let tight = tight
+                //     || matches!(
+                //         node.parent().map(|n| n.data.borrow().value.clone()),
+                //         Some(NodeValue::DescriptionTerm)
+                //     );
 
                 if !tight {
                     if entering {
diff --git a/src/nodes.rs b/src/nodes.rs
index 95b58a59..d2964866 100644
--- a/src/nodes.rs
+++ b/src/nodes.rs
@@ -307,6 +307,10 @@ pub struct NodeDescriptionItem {
 
     /// Number of characters between the start of the list marker and the item text (including the list marker(s)).
     pub padding: usize,
+
+    /// Whether the list is [tight](https://github.github.com/gfm/#tight), i.e. whether the
+    /// paragraphs are wrapped in `<p>` tags when formatted as HTML.
+    pub tight: bool,
 }
 
 /// The type of list.
diff --git a/src/parser/mod.rs b/src/parser/mod.rs
index 0b8f3171..6993a145 100644
--- a/src/parser/mod.rs
+++ b/src/parser/mod.rs
@@ -288,7 +288,7 @@ pub struct ExtensionOptions {
     /// let mut options = Options::default();
     /// options.extension.description_lists = true;
     /// assert_eq!(markdown_to_html("Term\n\n: Definition", &options),
-    ///            "<dl><dt>Term</dt>\n<dd>\n<p>Definition</p>\n</dd>\n</dl>\n");
+    ///            "<dl>\n<dt>Term</dt>\n<dd>\n<p>Definition</p>\n</dd>\n</dl>\n");
     /// ```
     pub description_lists: bool,
 
@@ -1503,10 +1503,13 @@ impl<'a, 'o, 'c: 'o> Parser<'a, 'o, 'c> {
                 container.data.borrow_mut().internal_offset = matched;
             } else if !indented
                 && self.options.extension.description_lists
-                && line[self.first_nonspace] == b':'
+                && unwrap_into(
+                    scanners::description_item_start(&line[self.first_nonspace..]),
+                    &mut matched,
+                )
                 && self.parse_desc_list_details(container)
             {
-                let offset = self.first_nonspace + 1 - self.offset;
+                let offset = self.first_nonspace + matched - self.offset;
                 self.advance_offset(line, offset, false);
                 if strings::is_space_or_tab(line[self.offset]) {
                     self.advance_offset(line, 1, true);
@@ -1748,10 +1751,19 @@ impl<'a, 'o, 'c: 'o> Parser<'a, 'o, 'c> {
         }
     }
 
-    fn parse_desc_list_details(&mut self, container: &mut &'a AstNode<'a>) -> bool {
+    fn parse_desc_list_details(&mut self, node: &mut &'a AstNode<'a>) -> bool {
+        let container = node;
+        let mut tight = false;
+        
         let last_child = match container.last_child() {
             Some(lc) => lc,
-            None => return false,
+            None => {
+                // Happens when the detail line is directly after the term,
+                // without a blank line between.
+                tight = true;
+                *container = container.parent().unwrap();
+                container.last_child().unwrap()
+            }
         };
 
         if node_matches!(last_child, NodeValue::Paragraph) {
@@ -1799,6 +1811,7 @@ impl<'a, 'o, 'c: 'o> Parser<'a, 'o, 'c> {
             let metadata = NodeDescriptionItem {
                 marker_offset: self.indent,
                 padding: 2,
+                tight,
             };
 
             let item = self.add_child(
@@ -1816,6 +1829,50 @@ impl<'a, 'o, 'c: 'o> Parser<'a, 'o, 'c> {
             *container = details;
 
             true
+        } else if node_matches!(last_child, NodeValue::DescriptionItem(..)) {
+            // ORIGINAL CODE
+            let parent = last_child.parent().unwrap();
+            reopen_ast_nodes(parent);
+
+            let metadata = NodeDescriptionItem {
+                marker_offset: self.indent,
+                padding: 2,
+                tight,
+            };
+
+            let item = self.add_child(
+                parent,
+                NodeValue::DescriptionItem(metadata),
+                self.first_nonspace + 1,
+            );
+
+            let details =
+                self.add_child(item, NodeValue::DescriptionDetails, self.first_nonspace + 1);
+
+            *container = details;
+
+            true
+
+            // ATTEMPT 1
+            // reopen_ast_nodes(last_child);
+            // 
+            // let details =
+            //     self.add_child(last_child, NodeValue::DescriptionDetails, self.first_nonspace + 1);
+            // *container = details;
+            // 
+            // true
+            
+            // ATTEMPT 2
+            // let parent = last_child.parent().unwrap();
+            // let item = parent.last_child().unwrap();
+            // 
+            // reopen_ast_nodes(item);
+            // 
+            // let details =
+            //     self.add_child(item, NodeValue::DescriptionDetails, self.first_nonspace + 1);
+            // *container = details;
+            // 
+            // true
         } else {
             false
         }
diff --git a/src/scanners.re b/src/scanners.re
index 35bbc4f6..ecdcaa8c 100644
--- a/src/scanners.re
+++ b/src/scanners.re
@@ -431,4 +431,14 @@ pub fn tasklist(s: &[u8]) -> Option<(usize, u8)> {
 */
 }
 
+pub fn description_item_start(s: &[u8]) -> Option<usize> {
+    let mut cursor = 0;
+    let _marker = 0;
+    let len = s.len();
+/*!re2c
+    [:~] ([ \t]+|[\r\n])  { return Some(cursor); }
+    * { return None; }
+*/
+}
+
 // vim: set ft=rust:
diff --git a/src/scanners.rs b/src/scanners.rs
index 52b2a747..43e72ca6 100644
--- a/src/scanners.rs
+++ b/src/scanners.rs
@@ -1,4 +1,4 @@
-/* Generated by re2c 3.1 */
+/* Generated by re2c 3.0 */
 
 pub fn atx_heading_start(s: &[u8]) -> Option<usize> {
     let mut cursor = 0;
@@ -23848,4 +23848,102 @@ pub fn tasklist(s: &[u8]) -> Option<(usize, u8)> {
     }
 }
 
+pub fn description_item_start(s: &[u8]) -> Option<usize> {
+    let mut cursor = 0;
+    let _marker = 0;
+    let len = s.len();
+
+    {
+        #[allow(unused_assignments)]
+        let mut yych: u8 = 0;
+        let mut yystate: usize = 0;
+        'yyl: loop {
+            match yystate {
+                0 => {
+                    yych = unsafe {
+                        if cursor < len {
+                            *s.get_unchecked(cursor)
+                        } else {
+                            0
+                        }
+                    };
+                    cursor += 1;
+                    match yych {
+                        0x3A | 0x7E => {
+                            yystate = 3;
+                            continue 'yyl;
+                        }
+                        _ => {
+                            yystate = 1;
+                            continue 'yyl;
+                        }
+                    }
+                }
+                1 => {
+                    yystate = 2;
+                    continue 'yyl;
+                }
+                2 => {
+                    return None;
+                }
+                3 => {
+                    yych = unsafe {
+                        if cursor < len {
+                            *s.get_unchecked(cursor)
+                        } else {
+                            0
+                        }
+                    };
+                    match yych {
+                        0x09 | 0x20 => {
+                            cursor += 1;
+                            yystate = 4;
+                            continue 'yyl;
+                        }
+                        0x0A | 0x0D => {
+                            cursor += 1;
+                            yystate = 6;
+                            continue 'yyl;
+                        }
+                        _ => {
+                            yystate = 2;
+                            continue 'yyl;
+                        }
+                    }
+                }
+                4 => {
+                    yych = unsafe {
+                        if cursor < len {
+                            *s.get_unchecked(cursor)
+                        } else {
+                            0
+                        }
+                    };
+                    match yych {
+                        0x09 | 0x20 => {
+                            cursor += 1;
+                            yystate = 4;
+                            continue 'yyl;
+                        }
+                        _ => {
+                            yystate = 5;
+                            continue 'yyl;
+                        }
+                    }
+                }
+                5 => {
+                    return Some(cursor);
+                }
+                6 => {
+                    yystate = 5;
+                    continue 'yyl;
+                }
+                _ => {
+                    panic!("internal lexer error")
+                }
+            }
+        }
+    }
+}
+
 // vim: set ft=rust:
diff --git a/src/tests/description_lists.rs b/src/tests/description_lists.rs
index 06970fc0..13f11e9f 100644
--- a/src/tests/description_lists.rs
+++ b/src/tests/description_lists.rs
@@ -14,7 +14,7 @@ fn description_lists() {
             ": Definition 2\n"
         ),
         concat!(
-            "<dl>",
+            "<dl>\n",
             "<dt>Term 1</dt>\n",
             "<dd>\n",
             "<p>Definition 1</p>\n",
@@ -41,7 +41,7 @@ fn description_lists() {
             "<ul>\n",
             "<li>\n",
             "<p>Nested</p>\n",
-            "<dl>",
+            "<dl>\n",
             "<dt>Term 1</dt>\n",
             "<dd>\n",
             "<p>Definition 1</p>\n",
diff --git a/src/tests/fixtures/description_lists.md b/src/tests/fixtures/description_lists.md
new file mode 100644
index 00000000..5f689014
--- /dev/null
+++ b/src/tests/fixtures/description_lists.md
@@ -0,0 +1,298 @@
+---
+title: Description / defintition lists
+based_on: https://github.com/jgm/commonmark-hs/blob/master/commonmark-extensions/test/definition_lists.md
+---
+
+## Definition lists
+
+The term is given on a line by itself, followed by
+one or more definitions. Each definition must begin
+with `:` (after 0-2 spaces); subsequent lines must
+be indented unless they are lazy paragraph
+continuations.
+
+The list is tight if there is no blank line between
+the term and the first definition, otherwise loose.
+
+```````````````````````````````` example
+apple
+:   red fruit
+
+orange
+:   orange fruit
+.
+<dl>
+<dt>apple</dt>
+<dd>red fruit</dd>
+<dt>orange</dt>
+<dd>orange fruit</dd>
+</dl>
+````````````````````````````````
+
+Loose:
+
+```````````````````````````````` example
+apple
+
+:   red fruit
+
+orange
+
+:   orange fruit
+.
+<dl>
+<dt>apple</dt>
+<dd>
+<p>red fruit</p>
+</dd>
+<dt>orange</dt>
+<dd>
+<p>orange fruit</p>
+</dd>
+</dl>
+````````````````````````````````
+
+Indented marker:
+
+```````````````````````````````` example
+apple
+  : red fruit
+
+orange
+  : orange fruit
+.
+<dl>
+<dt>apple</dt>
+<dd>red fruit</dd>
+<dt>orange</dt>
+<dd>orange fruit</dd>
+</dl>
+````````````````````````````````
+
+```````````````````````````````` example
+apple
+
+ : red fruit
+
+orange
+
+ : orange fruit
+.
+<dl>
+<dt>apple</dt>
+<dd>
+<p>red fruit</p>
+</dd>
+<dt>orange</dt>
+<dd>
+<p>orange fruit</p>
+</dd>
+</dl>
+````````````````````````````````
+
+Multiple blocks in a definition:
+
+```````````````````````````````` example
+*apple*
+
+:   red fruit
+
+    contains seeds,
+    crisp, pleasant to taste
+
+*orange*
+
+:   orange fruit
+
+        { orange code block }
+
+    > orange block quote
+.
+<dl>
+<dt><em>apple</em></dt>
+<dd>
+<p>red fruit</p>
+<p>contains seeds,
+crisp, pleasant to taste</p>
+</dd>
+<dt><em>orange</em></dt>
+<dd>
+<p>orange fruit</p>
+<pre><code>{ orange code block }
+</code></pre>
+<blockquote>
+<p>orange block quote</p>
+</blockquote>
+</dd>
+</dl>
+````````````````````````````````
+
+Nested lists:
+
+```````````````````````````````` example
+term
+
+:   1. Para one
+
+       Para two
+.
+<dl>
+<dt>term</dt>
+<dd>
+<ol>
+<li>
+<p>Para one</p>
+<p>Para two</p>
+</li>
+</ol>
+</dd>
+</dl>
+````````````````````````````````
+
+Multiple definitions, tight:
+
+```````````````````````````````` example
+apple
+:   red fruit
+:   computer company
+
+orange
+:   orange fruit
+:   telecom company
+.
+<dl>
+<dt>apple</dt>
+<dd>red fruit</dd>
+<dd>computer company</dd>
+<dt>orange</dt>
+<dd>orange fruit</dd>
+<dd>telecom company</dd>
+</dl>
+````````````````````````````````
+
+Multiple definitions, loose:
+
+```````````````````````````````` example
+apple
+
+:   red fruit
+
+:   computer company
+
+orange
+
+:   orange fruit
+:   telecom company
+.
+<dl>
+<dt>apple</dt>
+<dd>
+<p>red fruit</p>
+</dd>
+<dd>
+<p>computer company</p>
+</dd>
+<dt>orange</dt>
+<dd>
+<p>orange fruit</p>
+</dd>
+<dd>
+<p>telecom company</p>
+</dd>
+</dl>
+````````````````````````````````
+
+Lazy line continuations:
+
+```````````````````````````````` example
+apple
+
+:   red fruit
+
+:   computer
+company
+
+orange
+
+:   orange
+fruit
+:   telecom company
+.
+<dl>
+<dt>apple</dt>
+<dd>
+<p>red fruit</p>
+</dd>
+<dd>
+<p>computer
+company</p>
+</dd>
+<dt>orange</dt>
+<dd>
+<p>orange
+fruit</p>
+</dd>
+<dd>
+<p>telecom company</p>
+</dd>
+</dl>
+````````````````````````````````
+
+
+
+`~` may be used as a marker instead of `:`:
+
+```````````````````````````````` example
+apple
+  ~ red fruit
+
+orange
+  ~ orange fruit
+.
+<dl>
+<dt>apple</dt>
+<dd>red fruit</dd>
+<dt>orange</dt>
+<dd>orange fruit</dd>
+</dl>
+````````````````````````````````
+
+Definition terms may span multiple lines:
+
+```````````````````````````````` example
+a
+b\
+c
+
+:   foo
+.
+<dl>
+<dt>a
+b<br />
+c</dt>
+<dd>
+<p>foo</p>
+</dd>
+</dl>
+````````````````````````````````
+
+Definition list with preceding paragraph
+(<https://github.com/jgm/commonmark-hs/issues/35>):
+
+```````````````````````````````` example
+Foo
+
+bar
+:   baz
+
+bim
+:   bor
+.
+<p>Foo</p>
+<dl>
+<dt>bar</dt>
+<dd>baz</dd>
+<dt>bim</dt>
+<dd>bor</dd>
+</dl>
+````````````````````````````````