diff --git a/library/core/src/num/int_macros.rs b/library/core/src/num/int_macros.rs
index 5683d5ec92dc7..10efb8aff4a56 100644
--- a/library/core/src/num/int_macros.rs
+++ b/library/core/src/num/int_macros.rs
@@ -177,14 +177,14 @@ macro_rules! int_impl {
         ///
         #[doc = concat!("let n: ", stringify!($SelfT), " = 0b_01100100;")]
         ///
-        /// assert_eq!(n.isolate_most_significant_one(), 0b_01000000);
-        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_most_significant_one(), 0);")]
+        /// assert_eq!(n.isolate_highest_one(), 0b_01000000);
+        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_highest_one(), 0);")]
         /// ```
         #[unstable(feature = "isolate_most_least_significant_one", issue = "136909")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        pub const fn isolate_most_significant_one(self) -> Self {
+        pub const fn isolate_highest_one(self) -> Self {
             self & (((1 as $SelfT) << (<$SelfT>::BITS - 1)).wrapping_shr(self.leading_zeros()))
         }
 
@@ -198,14 +198,14 @@ macro_rules! int_impl {
         ///
         #[doc = concat!("let n: ", stringify!($SelfT), " = 0b_01100100;")]
         ///
-        /// assert_eq!(n.isolate_least_significant_one(), 0b_00000100);
-        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_least_significant_one(), 0);")]
+        /// assert_eq!(n.isolate_lowest_one(), 0b_00000100);
+        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_lowest_one(), 0);")]
         /// ```
         #[unstable(feature = "isolate_most_least_significant_one", issue = "136909")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        pub const fn isolate_least_significant_one(self) -> Self {
+        pub const fn isolate_lowest_one(self) -> Self {
             self & self.wrapping_neg()
         }
 
diff --git a/library/core/src/num/nonzero.rs b/library/core/src/num/nonzero.rs
index f793602de5087..2d3a680b348c1 100644
--- a/library/core/src/num/nonzero.rs
+++ b/library/core/src/num/nonzero.rs
@@ -629,7 +629,7 @@ macro_rules! nonzero_integer {
             #[doc = concat!("let a = NonZero::<", stringify!($Int), ">::new(0b_01100100)?;")]
             #[doc = concat!("let b = NonZero::<", stringify!($Int), ">::new(0b_01000000)?;")]
             ///
-            /// assert_eq!(a.isolate_most_significant_one(), b);
+            /// assert_eq!(a.isolate_highest_one(), b);
             /// # Some(())
             /// # }
             /// ```
@@ -637,7 +637,7 @@ macro_rules! nonzero_integer {
             #[must_use = "this returns the result of the operation, \
                         without modifying the original"]
             #[inline(always)]
-            pub const fn isolate_most_significant_one(self) -> Self {
+            pub const fn isolate_highest_one(self) -> Self {
                 let n = self.get() & (((1 as $Int) << (<$Int>::BITS - 1)).wrapping_shr(self.leading_zeros()));
 
                 // SAFETY:
@@ -659,7 +659,7 @@ macro_rules! nonzero_integer {
             #[doc = concat!("let a = NonZero::<", stringify!($Int), ">::new(0b_01100100)?;")]
             #[doc = concat!("let b = NonZero::<", stringify!($Int), ">::new(0b_00000100)?;")]
             ///
-            /// assert_eq!(a.isolate_least_significant_one(), b);
+            /// assert_eq!(a.isolate_lowest_one(), b);
             /// # Some(())
             /// # }
             /// ```
@@ -667,7 +667,7 @@ macro_rules! nonzero_integer {
             #[must_use = "this returns the result of the operation, \
                         without modifying the original"]
             #[inline(always)]
-            pub const fn isolate_least_significant_one(self) -> Self {
+            pub const fn isolate_lowest_one(self) -> Self {
                 let n = self.get();
                 let n = n & n.wrapping_neg();
 
diff --git a/library/core/src/num/uint_macros.rs b/library/core/src/num/uint_macros.rs
index 584cd60fbe5cc..5a41a302916a8 100644
--- a/library/core/src/num/uint_macros.rs
+++ b/library/core/src/num/uint_macros.rs
@@ -229,14 +229,14 @@ macro_rules! uint_impl {
         ///
         #[doc = concat!("let n: ", stringify!($SelfT), " = 0b_01100100;")]
         ///
-        /// assert_eq!(n.isolate_most_significant_one(), 0b_01000000);
-        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_most_significant_one(), 0);")]
+        /// assert_eq!(n.isolate_highest_one(), 0b_01000000);
+        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_highest_one(), 0);")]
         /// ```
         #[unstable(feature = "isolate_most_least_significant_one", issue = "136909")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        pub const fn isolate_most_significant_one(self) -> Self {
+        pub const fn isolate_highest_one(self) -> Self {
             self & (((1 as $SelfT) << (<$SelfT>::BITS - 1)).wrapping_shr(self.leading_zeros()))
         }
 
@@ -250,14 +250,14 @@ macro_rules! uint_impl {
         ///
         #[doc = concat!("let n: ", stringify!($SelfT), " = 0b_01100100;")]
         ///
-        /// assert_eq!(n.isolate_least_significant_one(), 0b_00000100);
-        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_least_significant_one(), 0);")]
+        /// assert_eq!(n.isolate_lowest_one(), 0b_00000100);
+        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_lowest_one(), 0);")]
         /// ```
         #[unstable(feature = "isolate_most_least_significant_one", issue = "136909")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        pub const fn isolate_least_significant_one(self) -> Self {
+        pub const fn isolate_lowest_one(self) -> Self {
             self & self.wrapping_neg()
         }
 
diff --git a/library/coretests/tests/nonzero.rs b/library/coretests/tests/nonzero.rs
index 00232c9b7061a..60e1149f6e6bb 100644
--- a/library/coretests/tests/nonzero.rs
+++ b/library/coretests/tests/nonzero.rs
@@ -321,7 +321,7 @@ fn nonzero_trailing_zeros() {
 }
 
 #[test]
-fn test_nonzero_isolate_most_significant_one() {
+fn test_nonzero_isolate_highest_one() {
     // Signed most significant one
     macro_rules! nonzero_int_impl {
         ($($T:ty),+) => {
@@ -335,8 +335,8 @@ fn test_nonzero_isolate_most_significant_one() {
                     let mut i = 0;
                     while i < <$T>::BITS {
                         assert_eq!(
-                            NonZero::<$T>::new(BITS >> i).unwrap().isolate_most_significant_one(),
-                            NonZero::<$T>::new(MOST_SIG_ONE >> i).unwrap().isolate_most_significant_one()
+                            NonZero::<$T>::new(BITS >> i).unwrap().isolate_highest_one(),
+                            NonZero::<$T>::new(MOST_SIG_ONE >> i).unwrap().isolate_highest_one()
                         );
                         i += 1;
                     }
@@ -356,8 +356,8 @@ fn test_nonzero_isolate_most_significant_one() {
                     let mut i = 0;
                     while i < <$T>::BITS {
                         assert_eq!(
-                            NonZero::<$T>::new(BITS >> i).unwrap().isolate_most_significant_one(),
-                            NonZero::<$T>::new(MOST_SIG_ONE >> i).unwrap().isolate_most_significant_one(),
+                            NonZero::<$T>::new(BITS >> i).unwrap().isolate_highest_one(),
+                            NonZero::<$T>::new(MOST_SIG_ONE >> i).unwrap().isolate_highest_one(),
                         );
                         i += 1;
                     }
@@ -371,7 +371,7 @@ fn test_nonzero_isolate_most_significant_one() {
 }
 
 #[test]
-fn test_nonzero_isolate_least_significant_one() {
+fn test_nonzero_isolate_lowest_one() {
     // Signed least significant one
     macro_rules! nonzero_int_impl {
         ($($T:ty),+) => {
@@ -385,8 +385,8 @@ fn test_nonzero_isolate_least_significant_one() {
                     let mut i = 0;
                     while i < <$T>::BITS {
                         assert_eq!(
-                            NonZero::<$T>::new(BITS << i).unwrap().isolate_least_significant_one(),
-                            NonZero::<$T>::new(LEAST_SIG_ONE << i).unwrap().isolate_least_significant_one()
+                            NonZero::<$T>::new(BITS << i).unwrap().isolate_lowest_one(),
+                            NonZero::<$T>::new(LEAST_SIG_ONE << i).unwrap().isolate_lowest_one()
                         );
                         i += 1;
                     }
@@ -406,8 +406,8 @@ fn test_nonzero_isolate_least_significant_one() {
                     let mut i = 0;
                     while i < <$T>::BITS {
                         assert_eq!(
-                            NonZero::<$T>::new(BITS << i).unwrap().isolate_least_significant_one(),
-                            NonZero::<$T>::new(LEAST_SIG_ONE << i).unwrap().isolate_least_significant_one(),
+                            NonZero::<$T>::new(BITS << i).unwrap().isolate_lowest_one(),
+                            NonZero::<$T>::new(LEAST_SIG_ONE << i).unwrap().isolate_lowest_one(),
                         );
                         i += 1;
                     }
diff --git a/library/coretests/tests/num/int_macros.rs b/library/coretests/tests/num/int_macros.rs
index 41d399c1ad9f5..ca32fce861f8c 100644
--- a/library/coretests/tests/num/int_macros.rs
+++ b/library/coretests/tests/num/int_macros.rs
@@ -194,7 +194,7 @@ macro_rules! int_module {
         }
 
         #[test]
-        fn test_isolate_most_significant_one() {
+        fn test_isolate_highest_one() {
             const BITS: $T = -1;
             const MOST_SIG_ONE: $T = 1 << (<$T>::BITS - 1);
 
@@ -203,15 +203,15 @@ macro_rules! int_module {
             let mut i = 0;
             while i < <$T>::BITS {
                 assert_eq!(
-                    (BITS >> i).isolate_most_significant_one(),
-                    (MOST_SIG_ONE >> i).isolate_most_significant_one()
+                    (BITS >> i).isolate_highest_one(),
+                    (MOST_SIG_ONE >> i).isolate_highest_one()
                 );
                 i += 1;
             }
         }
 
         #[test]
-        fn test_isolate_least_significant_one() {
+        fn test_isolate_lowest_one() {
             const BITS: $T = -1;
             const LEAST_SIG_ONE: $T = 1;
 
@@ -220,8 +220,8 @@ macro_rules! int_module {
             let mut i = 0;
             while i < <$T>::BITS {
                 assert_eq!(
-                    (BITS << i).isolate_least_significant_one(),
-                    (LEAST_SIG_ONE << i).isolate_least_significant_one()
+                    (BITS << i).isolate_lowest_one(),
+                    (LEAST_SIG_ONE << i).isolate_lowest_one()
                 );
                 i += 1;
             }
diff --git a/library/coretests/tests/num/uint_macros.rs b/library/coretests/tests/num/uint_macros.rs
index 7e02027bdd6a1..8f389de70aa2e 100644
--- a/library/coretests/tests/num/uint_macros.rs
+++ b/library/coretests/tests/num/uint_macros.rs
@@ -151,7 +151,7 @@ macro_rules! uint_module {
         }
 
         #[test]
-        fn test_isolate_most_significant_one() {
+        fn test_isolate_highest_one() {
             const BITS: $T = <$T>::MAX;
             const MOST_SIG_ONE: $T = 1 << (<$T>::BITS - 1);
 
@@ -160,15 +160,15 @@ macro_rules! uint_module {
             let mut i = 0;
             while i < <$T>::BITS {
                 assert_eq!(
-                    (BITS >> i).isolate_most_significant_one(),
-                    (MOST_SIG_ONE >> i).isolate_most_significant_one(),
+                    (BITS >> i).isolate_highest_one(),
+                    (MOST_SIG_ONE >> i).isolate_highest_one(),
                 );
                 i += 1;
             }
         }
 
         #[test]
-        fn test_isolate_least_significant_one() {
+        fn test_isolate_lowest_one() {
             const BITS: $T = <$T>::MAX;
             const LEAST_SIG_ONE: $T = 1;
 
@@ -177,8 +177,8 @@ macro_rules! uint_module {
             let mut i = 0;
             while i < <$T>::BITS {
                 assert_eq!(
-                    (BITS << i).isolate_least_significant_one(),
-                    (LEAST_SIG_ONE << i).isolate_least_significant_one(),
+                    (BITS << i).isolate_lowest_one(),
+                    (LEAST_SIG_ONE << i).isolate_lowest_one(),
                 );
                 i += 1;
             }