diff --git a/man2/mmap.2 b/man2/mmap.2
index 88468887c..ea64eb8f0 100644
--- a/man2/mmap.2
+++ b/man2/mmap.2
@@ -64,7 +64,8 @@ argument specifies the length of the mapping (which must be greater than 0).
 If
 .I addr
 is NULL,
-then the kernel chooses the address at which to create the mapping;
+then the kernel chooses the (page-aligned) address
+at which to create the mapping;
 this is the most portable method of creating a new mapping.
 If
 .I addr