/ Dictionary / Index P presidio: Meaning and Definition of Find definitions for: pre•sid•i•o Pronunciation: (pri-sid'ē-ō" Sp. pre-sē'&thslashyô), [key] — pl. -sid•i•os a garrisoned fort; military post. a Spanish penal settlement. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: presidio (Thesaurus) presidentship presidium Related Content Daily Word Quiz: acquiesce Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language