diff --git a/library/std/src/sys/hermit/thread.rs b/library/std/src/sys/hermit/thread.rs
index 8be25f84999d2..81b21fbbb1656 100644
--- a/library/std/src/sys/hermit/thread.rs
+++ b/library/std/src/sys/hermit/thread.rs
@@ -97,7 +97,7 @@ impl Thread {
     }
 }
 
-pub fn available_concurrency() -> io::Result<NonZeroUsize> {
+pub fn available_parallelism() -> io::Result<NonZeroUsize> {
     unsupported()
 }
 
diff --git a/library/std/src/sys/sgx/thread.rs b/library/std/src/sys/sgx/thread.rs
index cbb8ba964018a..d745a61961404 100644
--- a/library/std/src/sys/sgx/thread.rs
+++ b/library/std/src/sys/sgx/thread.rs
@@ -137,7 +137,7 @@ impl Thread {
     }
 }
 
-pub fn available_concurrency() -> io::Result<NonZeroUsize> {
+pub fn available_parallelism() -> io::Result<NonZeroUsize> {
     unsupported()
 }
 
diff --git a/library/std/src/sys/unix/thread.rs b/library/std/src/sys/unix/thread.rs
index 133ad3ea420b8..6fae31fa71e3b 100644
--- a/library/std/src/sys/unix/thread.rs
+++ b/library/std/src/sys/unix/thread.rs
@@ -263,7 +263,7 @@ impl Drop for Thread {
     }
 }
 
-pub fn available_concurrency() -> io::Result<NonZeroUsize> {
+pub fn available_parallelism() -> io::Result<NonZeroUsize> {
     cfg_if::cfg_if! {
         if #[cfg(any(
             target_os = "android",
diff --git a/library/std/src/sys/unsupported/thread.rs b/library/std/src/sys/unsupported/thread.rs
index dc75d4ee6725c..a8db251de2017 100644
--- a/library/std/src/sys/unsupported/thread.rs
+++ b/library/std/src/sys/unsupported/thread.rs
@@ -31,7 +31,7 @@ impl Thread {
     }
 }
 
-pub fn available_concurrency() -> io::Result<NonZeroUsize> {
+pub fn available_parallelism() -> io::Result<NonZeroUsize> {
     unsupported()
 }
 
diff --git a/library/std/src/sys/wasi/thread.rs b/library/std/src/sys/wasi/thread.rs
index 9ec02bbec2644..2e4e474c4492c 100644
--- a/library/std/src/sys/wasi/thread.rs
+++ b/library/std/src/sys/wasi/thread.rs
@@ -64,7 +64,7 @@ impl Thread {
     }
 }
 
-pub fn available_concurrency() -> io::Result<NonZeroUsize> {
+pub fn available_parallelism() -> io::Result<NonZeroUsize> {
     unsupported()
 }
 
diff --git a/library/std/src/sys/wasm/atomics/thread.rs b/library/std/src/sys/wasm/atomics/thread.rs
index a66ab0837570d..16418a06226e4 100644
--- a/library/std/src/sys/wasm/atomics/thread.rs
+++ b/library/std/src/sys/wasm/atomics/thread.rs
@@ -40,7 +40,7 @@ impl Thread {
     pub fn join(self) {}
 }
 
-pub fn available_concurrency() -> io::Result<NonZeroUsize> {
+pub fn available_parallelism() -> io::Result<NonZeroUsize> {
     unsupported()
 }
 
diff --git a/library/std/src/sys/windows/thread.rs b/library/std/src/sys/windows/thread.rs
index a5293133b3ab0..75f70c2076ee1 100644
--- a/library/std/src/sys/windows/thread.rs
+++ b/library/std/src/sys/windows/thread.rs
@@ -100,7 +100,7 @@ impl Thread {
     }
 }
 
-pub fn available_concurrency() -> io::Result<NonZeroUsize> {
+pub fn available_parallelism() -> io::Result<NonZeroUsize> {
     let res = unsafe {
         let mut sysinfo: c::SYSTEM_INFO = crate::mem::zeroed();
         c::GetSystemInfo(&mut sysinfo);
diff --git a/library/std/src/thread/mod.rs b/library/std/src/thread/mod.rs
index f44df845bf4dd..e24a3cb898627 100644
--- a/library/std/src/thread/mod.rs
+++ b/library/std/src/thread/mod.rs
@@ -1455,12 +1455,14 @@ fn _assert_sync_and_send() {
 ///
 /// ```
 /// # #![allow(dead_code)]
-/// #![feature(available_concurrency)]
+/// #![feature(available_parallelism)]
 /// use std::thread;
 ///
-/// let count = thread::available_concurrency().map(|n| n.get()).unwrap_or(1);
+/// let count = thread::available_parallelism().map(|n| n.get()).unwrap_or(1);
 /// ```
-#[unstable(feature = "available_concurrency", issue = "74479")]
-pub fn available_concurrency() -> io::Result<NonZeroUsize> {
-    imp::available_concurrency()
+#[doc(alias = "hardware_concurrency")] // Alias for C++ `std::thread::hardware_concurrency`.
+#[doc(alias = "available_concurrency")] // Alias for a name we gave this API on unstable.
+#[unstable(feature = "available_parallelism", issue = "74479")]
+pub fn available_parallelism() -> io::Result<NonZeroUsize> {
+    imp::available_parallelism()
 }
diff --git a/library/test/src/helpers/concurrency.rs b/library/test/src/helpers/concurrency.rs
index c39a9b0ec0233..e25f524ec0566 100644
--- a/library/test/src/helpers/concurrency.rs
+++ b/library/test/src/helpers/concurrency.rs
@@ -9,6 +9,6 @@ pub fn get_concurrency() -> usize {
             _ => panic!("RUST_TEST_THREADS is `{}`, should be a positive integer.", value),
         }
     } else {
-        thread::available_concurrency().map(|n| n.get()).unwrap_or(1)
+        thread::available_parallelism().map(|n| n.get()).unwrap_or(1)
     }
 }
diff --git a/library/test/src/lib.rs b/library/test/src/lib.rs
index 251f099f28af4..6732c6c61c204 100644
--- a/library/test/src/lib.rs
+++ b/library/test/src/lib.rs
@@ -23,7 +23,7 @@
 #![feature(libc)]
 #![feature(rustc_private)]
 #![feature(nll)]
-#![feature(available_concurrency)]
+#![feature(available_parallelism)]
 #![feature(bench_black_box)]
 #![feature(internal_output_capture)]
 #![feature(panic_unwind)]
diff --git a/src/doc/rustc/src/tests/index.md b/src/doc/rustc/src/tests/index.md
index ec23d4fe0dbd3..04e20fdd41c0f 100644
--- a/src/doc/rustc/src/tests/index.md
+++ b/src/doc/rustc/src/tests/index.md
@@ -161,7 +161,7 @@ The following options affect how tests are executed.
 
 Sets the number of threads to use for running tests in parallel. By default,
 uses the amount of concurrency available on the hardware as indicated by
-[`available_concurrency`].
+[`available_parallelism`].
 
 This can also be specified with the `RUST_TEST_THREADS` environment variable.
 
@@ -265,7 +265,7 @@ Experimental support for using custom test harnesses is available on the
 
 [`--test` option]: ../command-line-arguments.md#option-test
 [`-Z panic-abort-tests`]: https://github.com/rust-lang/rust/issues/67650
-[`available_concurrency`]: ../../std/thread/fn.available_concurrency.html
+[`available_parallelism`]: ../../std/thread/fn.available_parallelism.html
 [`cargo test`]: ../../cargo/commands/cargo-test.html
 [`libtest`]: ../../test/index.html
 [`main` function]: ../../reference/crates-and-source-files.html#main-functions