diff --git a/lib/chibi/regexp.scm b/lib/chibi/regexp.scm
index 40ef0070..fc2a16b2 100644
--- a/lib/chibi/regexp.scm
+++ b/lib/chibi/regexp.scm
@@ -532,6 +532,9 @@
        (string-cursor>? i start)
        (char-word-constituent?
         (string-cursor-ref str (string-cursor-prev str i)))))
+(define (match/nwb str i ch start end matches)
+  (and (not (match/bow str i ch start end matches))
+       (not (match/eow str i ch start end matches))))
 (define (match/bog str i ch start end matches)
   (and (string-cursor<? i end)
        (or (string-cursor=? i start)
@@ -718,6 +721,7 @@
         ((eol) (make-char-state match/eol flags next))
         ((bow) (make-char-state match/bow flags next))
         ((eow) (make-char-state match/eow flags next))
+        ((nwb) (make-char-state match/nwb flags next))
         ((bog) (make-char-state match/bog flags next))
         ((eog) (make-char-state match/eog flags next))
         ((grapheme)
diff --git a/tests/regexp-tests.scm b/tests/regexp-tests.scm
index ef21d0e3..3698b43c 100644
--- a/tests/regexp-tests.scm
+++ b/tests/regexp-tests.scm
@@ -142,6 +142,9 @@
 (test-re #f
          '(: (* space) bow ($ (* alpha)) eow (* space))
          " abc.  ")
+(test-re-search '("foo") '(: "foo") " foo ")
+(test-re-search #f '(: nwb "foo" nwb) " foo ")
+(test-re-search '("foo") '(: nwb "foo" nwb) "xfoox")
 
 (test-re '("beef")
          '(* (/"af"))