1. [ adjective ] abnormally large
Related terms: large
2. [ adjective ] shockingly brutal or cruel
Synonyms: flagitious grievous heinous atrocious

"murder is an atrocious crime" "a grievous offense against morality" "a grievous crime" "no excess was too monstrous for them to commit"

Related terms: evil
3. [ adjective ] distorted and unnatural in shape or size; abnormal and hideous
Synonyms: grotesque unnatural

"tales of grotesque serpents eight fathoms long that churned the seas" "twisted into monstrous shapes"

Related terms: ugly
Similar spelling:   monstrously