tap 1 
(tăp)
(tăp)v. tapped, tap·ping, taps
v.tr.
1. To strike gently with a light blow or blows: I tapped you on the shoulder to get your attention.
2. To give a light rap with: tap a pencil.
3. To produce with a succession of light blows: tap out a rhythm.
4. To select, as for membership in an organization; designate. See Synonyms at appoint.
5.
a. To repair (shoe heels or toes) by applying a thin layer of leather or a substitute material.
b. To attach metal plates to (shoe toes or heels).
v.intr.
1. To deliver a gentle, light blow or blows.
2. To walk making light clicks.
3. To tap-dance.
n.
1.
a. A gentle blow.
b. The sound made by such a blow.
2.
a. A thin layer of leather or a substitute applied to a worn-down shoe heel or toe.
b. A metal plate attached to the toe or heel of a shoe, as for tap-dancing.
c. Tap dance.
3. Linguistics See flap.
[Middle English tappen, from Old French taper, of imitative origin.]