sewer vs toilet

sewer and toilet both are nouns.

Word	Noun	Adjective	Verb	Adverb
sewer	Yes	No	No	No
toilet	Yes	No	No	No

As nouns, sewer and toilet are synonyms defined as:

Other synonyms of sewer include gutter.

sewer (noun)	toilet (noun)
a waste pipe that carries away sewage or surface water	the act of dressing and preparing yourself
misfortune resulting in lost effort or money	a room or building equipped with one or more toilets
someone who sews	a plumbing fixture for defecation and urination
	misfortune resulting in lost effort or money