The Collaborative International Dictionary of English v.0.48:

Ctenoid \Cte"noid\ (t[=e]"noid or t[e^]n"oid), a. (Zool.)
   (a) Having a comblike margin, as a ctenoid scale.
   (b) Pertaining to the Ctenoidei. -- n. A ctenoidean.
       [1913 Webster]

WordNet (r) 3.0 (2006):

ctenoid
    adj 1: resembling a comb; having projections like the teeth of a
           comb [syn: ctenoid, comb-like]