To thrust forth; to emit; to push out.
To put force, ability, or anything of the nature of an active faculty; to put in vigorous action; to bring into active operation; as, to exert the strength of the body, limbs, faculties, or imagination; to exert the mind or the voice.
To put forth, as the result or exercise of effort; to bring to bear; to do or perform.
To put effort into.
make a great effort at a mental or physical task; "exert oneself"