verb
-plies; -plied; -plying
[no obj] :to ask formally for something (such as a job, admission to a school, a loan, etc.) usually in writing
[+ obj] :to put or spread (something) on a surface, a part of the body, etc.
[+ obj] :to cause (force, pressure, etc.) to have an effect or to be felt
[+ obj] :to use (an idea, method, law, etc.) in a particular situation
[+ obj] :to cause (the brakes of a vehicle) to work
[no obj] :to have an effect on someone or something
to use a word, name, etc., to describe someone or something - usually + to; [no obj]
apply yourself
to make yourself work hard in order to complete something successfully