sump vs cesspool

sump and cesspool both are nouns.

Word	Noun	Adjective	Verb	Adverb
sump	Yes	No	No	No
cesspool	Yes	No	No	No

As nouns, sump and cesspool are synonyms defined as:

sump and cesspool: a covered cistern; waste water and sewage flow into it

Other synonyms of sump include cesspit, sink.

sump (noun)	cesspool (noun)
a well or other hole in which water has collected	a covered cistern; waste water and sewage flow into it
an oil reservoir in an internal combustion engine
a covered cistern; waste water and sewage flow into it