/ Dictionary / Index E ETO: Meaning and Definition of Find definitions for: ETO Pronunciation: [key] (in World War II) European Theater of Operations. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Etna étoile* 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