/ Dictionary / Index V vitellus: Meaning and Definition of Find definitions for: vi•tel•lus Pronunciation: (vi-tel'us, vī-), [key] — pl. -lus•es. the yolk of an egg. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: vitellus (Thesaurus) vitellogenesis vitiable Related Content Daily Word Quiz: vertigo Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language