sports coat vs sport jacket

sports coat and sport jacket both are nouns.

Word	Noun	Adjective	Verb	Adverb
sports coat	Yes	No	No	No
sport jacket	Yes	No	No	No

As nouns, sports coat and sport jacket are synonyms defined as:

sports coat and sport jacket: lightweight single-breasted jacket; often striped in the colors of a club or school

Other synonyms of sports coat include blazer, sport coat, sports jacket.

sports coat (noun)	sport jacket (noun)
lightweight single-breasted jacket; often striped in the colors of a club or school	lightweight single-breasted jacket; often striped in the colors of a club or school