Keelboat is a hyponym of flatboat.
As nouns the difference between flatboat and keelboat
is that flatboat is a boxy, flat-bottomed boat used for carrying livestock, freight, and people on rivers while keelboat is any sailboat having a keel (as opposed to a centerboard or daggerboard).
flatboat
English
Noun
(
en noun)
A boxy, flat-bottomed boat used for carrying livestock, freight, and people on rivers.
See also
* barge
keelboat
Noun
(
en noun)
(sailing) Any sailboat having a keel (as opposed to a centerboard or daggerboard).