/ Dictionary / Index C casinghead gas: Meaning and Definition of Find definitions for: cas'ing•head gas" Pronunciation: (kā'sing-hed"), [key] natural gas obtained from an oil well. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. casing casing knife Related Content Daily Word Quiz: procrastinate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language