adj. 25B6; adjective
a monstrous creature : GROTESQUE, hideous, ugly, ghastly, gruesome, horrible, horrific, horrifying, grisly, disgusting, repulsive, repellent, dreadful, frightening, terrifying, malformed, misshapen.
a monstrous tidal wave. : See huge .
monstrous acts of violence : APPALLING, heinous, egregious, evil, wicked, abominable, terrible, horrible, dreadful, vile, outrageous, shocking, disgraceful; unspeakable, despicable, vicious, savage, barbaric, barbarous, inhuman; Brit. informal beastly.
lovely, small.