APPLY', v.t. L. applico, of ad and plico, to fold or knit together; Gr. to knit, or twist; Eng. ply, display, and employ.
1. To lay on; to put one thing to another; as, to apply the hand to the breast; to apply medicaments to a diseased part of the body.
2. To use or employ for a particular purpose, or in a particular case; as, to apply a sum of money to the payment of a debt.
3. To put, refer or use, as suitable or relative to something; as, to apply the testimony to the case.
4. To fix the mind; to engage and employ with attention; as, apply thy heart to instruction.
5. To address or direct; as, "Sacred vows applied to Pluto."
6. To betake; to give the chief part of time and attention; as, to apply one's self to the study of botany. This is essentially the fourth sense.
7. To make application; to have recourse by request; as, to apply one's self to a counsellor for advice. This is generally used intransitively; as, to apply to a counsellor.
8. To busy; to keep at work; to ply. Obs.
Superseded by ply, which see.