remark vs platitude

remark and platitude both are nouns.

Word	Noun	Adjective	Verb	Adverb
remark	Yes	No	Yes	No
platitude	Yes	No	No	No

As nouns, platitude is a hyponym of remark; that is, platitude is a word with a more specific, narrower meaning than remark:

remark: a statement that expresses a personal opinion or belief or adds information
platitude: a trite or obvious remark

remark (noun)	platitude (noun)
explicit notice	a trite or obvious remark
a statement that expresses a personal opinion or belief or adds information

remark (verb)	platitude (verb)
make mention of
make or write a comment on