/ Dictionary / Index B baseless: Meaning and Definition of Find definitions for: base•less Pronunciation: (bās'lis), [key] — adj. having no base; without foundation; groundless: a baseless claim. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: baseless (Thesaurus) Basel base level Related Content Daily Word Quiz: tenacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language