GRUM Meaning of GRUM in English — grumly , adv. — grumness , n./grum/ , adj., grummer, grummest . (of a person's appearance) grim; glum; surly. [ 1630-40; prob. b. GRIM and GLUM ] Random House Webster's Unabridged English dictionary. Полный английский словарь Вебстер - Random House . 2012