/ Dictionary / Index E extension courses: Meaning and Definition of Find definitions for: exten'sion cours"es Pronunciation: [key] (in many universities and colleges) a program for persons not regularly enrolled as students, frequently provided through evening classes or classes in off-campus centers, or by correspondence. Cf. university extension. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. extension cord extension field Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language