/ Dictionary / Index B banner cloud: Meaning and Definition of Find definitions for: ban'ner cloud" Pronunciation: [key] a plume-shaped cloud extending downwind from an isolated mountain peak. Also calledCf. cap cloud (def. 1). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. banner banneret Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language