/ Dictionary / Index J Johnson grass: Meaning and Definition of Find definitions for: John'son grass" Pronunciation: [key] a sorghum, Sorghum halepense, that spreads by creeping rhizomes, grown for fodder. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Johnsonese Johnsonian Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language