a small, dark brown, subtropical seal of the genus Monachus: the three species, M. tropicalis of the Caribbean, M. schauinslandi of Hawaiian island regions, and M. monachus of the Mediterranean, are endangered.
[ 1835-45; appar. trans. of the NL genus name Monachus (see MONK), orig. a specific name ( Phoca monacha ), prob. in allusion to the animal's gray coloration and isolated breeding sites; cf. F moine, It monaco the monk seal, lit., monk ]