/ Dictionary / Index H holding tank: Meaning and Definition of Find definitions for: hold'ing tank" Pronunciation: [key] a tank for the temporary storage of a substance. Also calledtank (def. 4). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. holding pattern holdout Related Content Daily Word Quiz: cautious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language