/ Dictionary / Index A ad arbitrium*: Meaning and Definition of Find definitions for: ad ar•bi•tri•um Pronunciation: (äd är-bi'trē-oom" Eng. ad är-bi'trē-&schwam), [key] — Latin. Latin. at pleasure; at will. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Adar Adar Sheni Related Content Daily Word Quiz: pudgy Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language