boat paddle vs oar

boat paddle and oar both are nouns.

Word	Noun	Adjective	Verb	Adverb
boat paddle	Yes	No	No	No
oar	Yes	No	No	No

As nouns, oar is a hypernym of boat paddle; that is, oar is a word with a broader meaning than boat paddle:

boat paddle: a short light oar used without an oarlock to propel a canoe or small boat
oar: an implement used to propel or steer a boat

boat paddle (noun)	oar (noun)
a short light oar used without an oarlock to propel a canoe or small boat	an implement used to propel or steer a boat