autopilot vs inertial guidance system

autopilot and inertial guidance system both are nouns.

Word	Noun	Adjective	Verb	Adverb
autopilot	Yes	No	No	No
inertial guidance system	Yes	No	No	No

autopilot (noun)	inertial guidance system (noun)
a navigational device that automatically keeps ships or planes or spacecraft on a steady course	a system to control a plane or spacecraft; uses inertial forces
a cognitive state in which you act without self-awareness