growl / groul/ • v. [intr.] (of an animal, esp. a dog) make a low guttural sound of hostility in the throat: the dogs yapped and growled about his heels. ∎ [with direct speech] (of a person) say something in a low grating voice, typically in a threatening manner: “Keep out of this,” he growled. ∎ (of a thing) make a low or harsh rumbling sound, typically one that is felt to be threatening: thunder growls without warning from a summer sky. • n. a low guttural sound made in the throat, esp. by a dog. ∎ a similar sound made by a person, esp. to express hostility or anger. ∎ [in sing.] a low throaty sound made by a machine or engine: the growl of diesel engines. DERIVATIVES: growl·ing·ly adv.