platitudinal vs platitudinous

platitudinal and platitudinous both are adjectives.

Word	Noun	Adjective	Verb	Adverb
platitudinal	No	Yes	No	No
platitudinous	No	Yes	No	No

As adjectives, platitudinal and platitudinous are synonyms defined as:

platitudinal and platitudinous: dull and tiresome but with pretensions of significance or originality

Other synonyms of platitudinal include bromidic, corny.

platitudinal (adjective)	platitudinous (adjective)
dull and tiresome but with pretensions of significance or originality	dull and tiresome but with pretensions of significance or originality