/ Dictionary / Index E exponential horn: Meaning and Definition of Find definitions for: ex'ponen'tial horn' Pronunciation: [key] a loudspeaker horn with a cross-sectional area varying as a constant raised to an exponent proportional to the distance from the vertex. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. exponential function exponentiation Related Content Daily Word Quiz: neologism Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language