/ Dictionary / Index E expeditionary: Meaning and Definition of Find definitions for: ex•pe•di•tion•ar•y Pronunciation: (ek"spi-dish'u-ner"ē), [key] — adj. pertaining to or composing an expedition: an expeditionary force. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: expeditionary (Thesaurus) expedition expeditious Related Content Daily Word Quiz: stringent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language