haven vs seaport

haven and seaport both are nouns.

Word	Noun	Adjective	Verb	Adverb
haven	Yes	No	No	No
seaport	Yes	No	No	No

As nouns, haven and seaport are synonyms defined as:

haven and seaport: a sheltered port where ships can take on or discharge cargo

Other synonyms of haven include harbor, harbour.

haven (noun)	seaport (noun)
a shelter serving as a place of safety or sanctuary	a sheltered port where ships can take on or discharge cargo
a sheltered port where ships can take on or discharge cargo