ap·ply / əˈplī/ • v. (-plies, -plied) 1. [intr.] make a formal application or request: you need to apply to the local authorities for a grant. ∎  put oneself forward formally as a candidate for a job: she had applied for a number of positions.2. [intr.] be applicable or relevant: normal rules apply.3. [tr.] put or spread (something) on a surface: the sealer can be applied to new wood. ∎  administer: smooth over with a cloth, applying even pressure.4. (apply oneself) give one's full attention to a task; work hard.5. [tr.] bring or put into operation or practical use: the oil industry has failed to apply appropriate standards of care.

apply XIV. — OF. apl(o)ier :- L. applicāre, f. AP- + plicāre fold.
Hence appliance XVI.