trilby vs felt hat

trilby and felt hat both are nouns.

Word	Noun	Adjective	Verb	Adverb
trilby	Yes	No	No	No
felt hat	Yes	No	No	No

As nouns, trilby and felt hat are synonyms defined as:

Other synonyms of trilby include fedora, homburg, Stetson.

trilby (noun)	felt hat (noun)
a hat made of felt with a creased crown	a hat made of felt with a creased crown