leanleanleansleanedleantleaning1verb (leans, leaning, leantor leaned/, has leantor has leaned)1to not be straight; to bend forwards, backwards or to the side: She leaned out of the window and waved.2to put your body or a thing against another thing: Lean your bike against the wall.leanleanleanerleanest2adjective (leaner, leanest)1thin and healthy: He is tall and lean.2Lean meat does not have very much fat.