Source : Webster's Revised Unabridged Dictionary (1913)

Ceratobranchia \Cer`a*to*bran"chi*a\, n. pl. [NL., fr. Gr. ?, ?,
   horn + ?, n. pl., gills.] (Zo["o]l.)
   A group of nudibranchiate Mollusca having on the back
   papilliform or branched organs serving as gills.