knife-handle vs razor clam

knife-handle and razor clam both are nouns.

Word	Noun	Adjective	Verb	Adverb
knife-handle	Yes	No	No	No
razor clam	Yes	No	No	No

As nouns, knife-handle and razor clam are synonyms defined as:

knife-handle and razor clam: marine clam having a long narrow curved thin shell

Other synonyms of knife-handle include jackknife clam.

knife-handle (noun)	razor clam (noun)
marine clam having a long narrow curved thin shell	marine clam having a long narrow curved thin shell