chip vs chip at

chip is a noun but chip at is not a noun.

Word	Noun	Adjective	Verb	Adverb
chip	Yes	No	Yes	No
chip at	No	No	Yes	No

chip (noun)	chip at (noun)
the act of chipping something
(golf) a low running approach shot
electronic equipment consisting of a small crystal of a silicon semiconductor fabricated to carry out a number of electronic functions in an integrated circuit
a small disk-shaped counter used to represent money when gambling
a triangular wooden float attached to the end of a log line
a mark left after a small piece has been chopped or broken off of something
a thin crisp slice of potato fried in deep fat
a small fragment of something broken off from the whole
a piece of dried bovine dung

chip (verb)	chip at (verb)
break a small piece off from	engrave or cut by chipping away at a surface
break off (a piece from a whole)
form by chipping
cut a nick into
play a chip shot