/ Dictionary / Index A aerarium: Meaning and Definition of Find definitions for: ae•rar•i•um Pronunciation: (ē-râr'ē-um), [key] — pl. ae•rar•i•a the state treasury in ancient Rome. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. aerarian aerate Related Content Daily Word Quiz: alacrity Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language