tholepin vs oarlock

tholepin and oarlock both are nouns.

Word	Noun	Adjective	Verb	Adverb
tholepin	Yes	No	No	No
oarlock	Yes	No	No	No

As nouns, tholepin and oarlock are synonyms defined as:

tholepin and oarlock: a holder attached to the gunwale of a boat that holds the oar in place and acts as a fulcrum for rowing

Other synonyms of tholepin include peg, pin, rowlock, thole.

tholepin (noun)	oarlock (noun)
a holder attached to the gunwale of a boat that holds the oar in place and acts as a fulcrum for rowing	a holder attached to the gunwale of a boat that holds the oar in place and acts as a fulcrum for rowing