diff --git a/src/libstd/path.rs b/src/libstd/path.rs
index 95c8af664254..d215f368d1e6 100644
--- a/src/libstd/path.rs
+++ b/src/libstd/path.rs
@@ -254,7 +254,9 @@ pub fn is_separator(c: char) -> bool {
     c.is_ascii() && is_sep_byte(c as u8)
 }
 
-/// The primary separator for the current platform
+/// The primary separator of path components for the current platform.
+///
+/// For example, `/` on Unix and `\` on Windows.
 #[stable(feature = "rust1", since = "1.0.0")]
 pub const MAIN_SEPARATOR: char = ::sys::path::MAIN_SEP;