/ Dictionary / Index E elastic clause: Meaning and Definition of Find definitions for: elas'tic clause" Pronunciation: [key] a statement in the U.S. Constitution (Article I, Section 8) granting Congress the power to pass all laws necessary and proper for carrying out the enumerated list of powers. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. elastic elastic collision Related Content Daily Word Quiz: cetacean Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language