/ Dictionary / Index G grid circuit: Meaning and Definition of Find definitions for: grid' cir"cuit Pronunciation: [key] — Electronics. Electronics. that part of a circuit that contains the cathode and the grid of a vacuum tube. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. grid capacitor grid current 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