splenectomy vs excision

splenectomy and excision both are nouns.

Word	Noun	Adjective	Verb	Adverb
splenectomy	Yes	No	No	No
excision	Yes	No	No	No

As nouns, excision is a hypernym of splenectomy; that is, excision is a word with a broader meaning than splenectomy:

Other hypernyms of splenectomy include ablation, cutting out, extirpation.

splenectomy (noun)	excision (noun)
surgical removal of the spleen	surgical removal of a body part or tissue
	the act of pulling up or out; uprooting; cutting off from existence
	the act of banishing a member of a church from the communion of believers and the privileges of the church; cutting a person off from a religious society
	the omission that is made when an editorial change shortens a written passage