electric chair vs hot seat

electric chair and hot seat both are nouns.

Word	Noun	Adjective	Verb	Adverb
electric chair	Yes	No	No	No
hot seat	Yes	No	No	No

As nouns, electric chair and hot seat are synonyms defined as:

electric chair and hot seat: an instrument of execution by electrocution; resembles an ordinary seat for one person

Other synonyms of electric chair include chair, death chair.

electric chair (noun)	hot seat (noun)
an instrument of execution by electrocution; resembles an ordinary seat for one person	a difficult position where you are subjected to stress and criticism
	an instrument of execution by electrocution; resembles an ordinary seat for one person