lemongrass, (Cymbopogon citratus), also called sweet rush, species of oil grass in the family Poaceae, often used in cooking. At a distance, clusters of lemongrass in their native habitat look deceptively plain. Long skinny leaves of an unassuming green fan out from the stem, yet they release at a single touch a profuse lemon aroma that has made this pungent plant a staple of kitchens across South East Asia.
