computing vs security system

computing and security system both are nouns.

Word	Noun	Adjective	Verb	Adverb
computing	Yes	No	No	No
security system	Yes	No	No	No

computing (noun)	security system (noun)
the procedure of calculating; determining something by mathematical or logical methods	an electrical device that sets off an alarm when someone tries to break in
the branch of engineering science that studies (with the aid of computers) computable processes and structures	(computing) a system that enforces boundaries between computer networks