Part of speech: Adjective
distorted and unnatural in shape or size; abnormal and hideous
Example: tales of grotesque serpents eight fathoms long that churned the seas; twisted into monstrous shapes
Fantastical, Grotesque, Monstrous, Antic, Fantastic
The word "grotesque" comes from Italian grottesco, which comes from Middle French grotesque. Many other languages have similar words:
grotto – A related word in the same word family.
English has both Germanic and French words for the same things—'begin' vs 'commence', 'help' vs 'assist'.