Definition of "Apply" :

verb: ask (for something)

"Apply for a job."

verb: refer (a word or name) to a person or thing

verb: put into service; make work or employ for a particular purpose or for its inherent or natural purpose

"Apply a magnetic field here."

verb: apply to a surface

verb: give or convey physically

verb: ensure observance of laws and rules

"Apply the rules to everyone."

verb: avail oneself to

"Apply a principle."

verb: apply oneself to

"Please apply yourself to your homework."

verb: be pertinent or relevant or applicable

"The same laws apply to you!."

verb: be applicable to; as to an analysis