caustic remark vs sarcasm

caustic remark and sarcasm both are nouns.

Word	Noun	Adjective	Verb	Adverb
caustic remark	Yes	No	No	No
sarcasm	Yes	No	No	No

As nouns, caustic remark and sarcasm are synonyms defined as:

caustic remark and sarcasm: witty language used to convey insults or scorn

Other synonyms of caustic remark include irony, satire.

caustic remark (noun)	sarcasm (noun)
witty language used to convey insults or scorn	witty language used to convey insults or scorn