/ Dictionary / Index A acetabulum: Meaning and Definition of Find definitions for: ac•e•tab•u•lum Pronunciation: (as"i-tab'yu-lum), [key] — pl. -la the socket in the hipbone that receives the head of the thighbone. See illus. under any of the suction appendages of a leech, octopus, etc. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: acetabulum (Thesaurus) acetabuliform acetal Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language