being(s)
Devil fiend
animal, creature, monster, brute, fiend, glutton
Another name for a monster can be beast, creature*.
monster
Monster
another word for monster is ogre
There are various words that have similar meaning to the word monster; a monster can be described as a creature, possibly a mutant, an apparition, an abomination but it is actually the word monster itself which is most likely to be used to convey that the creature in question is terrifying. Abomination conveys loathing and hatred more than fear. Creature is relatively neutral, you could have any kind of feeling about a creature. Apparition is a more poetic form. Mutant is more clinical.
Yes, the word 'monster' is a noun, a word for an imaginary creature that is large, ugly, or frightening; a word for someone who is inhumanly cruel or wicked; a word for a person or a thing.
Another word for an underwater creature is a deep sea creature. Deep sea creatures include the cornuta, the giant isopod and the humpback anglerfish.
Monster
creatures
Beast.