pin vs peg

pin and peg both are nouns.

Word	Noun	Adjective	Verb	Adverb
pin	Yes	No	Yes	No
peg	Yes	No	Yes	No

As nouns, peg is a hyponym of pin; that is, peg is a word with a more specific, narrower meaning than pin:

pin: a small slender (often pointed) piece of wood or metal used to support or fasten or attach things
peg: a wooden pin pushed or driven into a surface

As nouns, pin and peg are synonyms defined as:

pin and peg: 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 pin include oarlock, rowlock, thole, tholepin.

As nouns, pin and peg are synonyms defined as:

Other synonyms of pin include stick.

As nouns, pin and peg are synonyms defined as:

pin and peg: small markers inserted into a surface to mark scores or define locations etc.

pin (noun)	peg (noun)
a small slender (often pointed) piece of wood or metal used to support or fasten or attach things	a wooden pin pushed or driven into a surface
a piece of jewelry that is pinned onto the wearer's garment	a holder attached to the gunwale of a boat that holds the oar in place and acts as a fulcrum for rowing
axis consisting of a short shaft that supports something that turns	regulator that can be turned to regulate the pitch of the strings of a stringed instrument
a holder attached to the gunwale of a boat that holds the oar in place and acts as a fulcrum for rowing	a prosthesis that replaces a missing leg
a club-shaped wooden object used in bowling; set up in triangular groups of ten as the target	informal terms for the leg
flagpole used to mark the position of the hole on a golf green	small markers inserted into a surface to mark scores or define locations etc.
cylindrical tumblers consisting of two parts that are held in place by springs; when they are aligned with a key the bolt can be thrown
informal terms for the leg
small markers inserted into a surface to mark scores or define locations etc.
when a wrestler's shoulders are forced to the mat

pin (verb)	peg (verb)
(chess) immobilize a piece	stabilize (the price of a commodity or an exchange rate) by legislation or market operations
attach or fasten with pins	fasten or secure with a wooden pin
pierce with a pin	pierce with a wooden pin or knock or thrust a wooden pin into
to hold fast or prevent from moving	succeed in obtaining a position