/ Dictionary / Index U ugly customer: Meaning and Definition of Find definitions for: ug'ly cus'tomer Pronunciation: [key] a hostile or dangerous person. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. ugly ugly duckling Related Content Daily Word Quiz: profiterole Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language