ketch vs sailing ship

ketch and sailing ship both are nouns.

Word	Noun	Adjective	Verb	Adverb
ketch	Yes	No	No	No
sailing ship	Yes	No	No	No

As nouns, sailing ship is a hypernym of ketch; that is, sailing ship is a word with a broader meaning than ketch:

ketch: a sailing vessel with two masts; the mizzen is forward of the rudderpost
sailing ship: a vessel that is powered by the wind; often having several masts

Other hypernyms of ketch include sailing vessel.

ketch (noun)	sailing ship (noun)
a sailing vessel with two masts; the mizzen is forward of the rudderpost	a vessel that is powered by the wind; often having several masts