diff --git a/share/man/man9/g_bio.9 b/share/man/man9/g_bio.9
index 5dd0df0fde46..b2da3b7bdf1a 100644
--- a/share/man/man9/g_bio.9
+++ b/share/man/man9/g_bio.9
@@ -76,7 +76,7 @@ Attributes are named by ascii strings and are stored in the
 .Va bio_attribute
 field.
 .It Dv BIO_FLUSH
-Tells underlying providers to flush theirs write cache.
+Tells underlying providers to flush their write caches.
 .El
 .It Va bio_flags
 Available flags: