/ Dictionary / Index S San Juan Mountains: Meaning and Definition of Find definitions for: San' Juan' Moun'tains Pronunciation: [key] a mountain range in SW Colorado and N New Mexico: a part of the Rocky Mountains. Highest peak, Uncompahgre Peak, 14,306 ft. (4360 m). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. San Juan Islands sank Related Content Daily Word Quiz: bungled Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language