solecism vs gaffe

solecism and gaffe both are nouns.

Word	Noun	Adjective	Verb	Adverb
solecism	Yes	No	No	No
gaffe	Yes	No	No	No

As nouns, solecism and gaffe are synonyms defined as:

Other synonyms of solecism include faux pas, gaucherie, slip.

solecism (noun)	gaffe (noun)
a socially awkward or tactless act	a socially awkward or tactless act