sympathectomy vs ablation

sympathectomy and ablation both are nouns.

Word	Noun	Adjective	Verb	Adverb
sympathectomy	Yes	No	No	No
ablation	Yes	No	No	No

As nouns, ablation is a hypernym of sympathectomy; that is, ablation is a word with a broader meaning than sympathectomy:

sympathectomy: surgical interruption of a nerve pathway in the sympathetic nervous system
ablation: surgical removal of a body part or tissue

Other hypernyms of sympathectomy include cutting out, excision, extirpation.

sympathectomy (noun)	ablation (noun)
surgical interruption of a nerve pathway in the sympathetic nervous system	surgical removal of a body part or tissue
	the erosive process that reduces the size of glaciers