n. a member of the Dinoflagellata, chiefly marine protozoa having two flagella. The dinoflagellates form a chief constituent of plankton. [ WordNet 1.5 ]
v. t. [ imp. & p. p. Flagellated p. pr. & vb. n. Flagellating ] [ L. flagellatus, p. p. of flagellare to scoure, fr. flagellum whip, dim. of flagrum whip, scoure; cf. fligere to strike. Cf. Flall. ] To whip; to scourge; to flog. [ 1913 Webster ]