tap

tap

1

water/gas

 [countable] especially British Englisha piece of equipment for controlling the flow of water, gas etc from a pipe or container [= faucetAmerican English]

Tap water (=water that comes out of a tap) is usually heavily treated with chemicals.

She went into the bathroom and turned on the taps.

kitchen/bath/garden tap

I washed my hands under the kitchen tap.

cold/hot tap (=the tap that cold or hot water comes from)

2

a light hit

 [countable] an act of hitting something lightly, especially to get someone's attention

tap at/on

She felt a tap on her shoulder.

There was a tap at the door.

3

 on tap

a) beer that is on tap comes from a barrel

b) informal something that is on tap is ready to use when you need it:

We've got all the information on tap.

4

dancing

also

 tap dancing

 [uncountable] dancing in which you wear special shoes with pieces of metal on the bottom which make a loud sharp sound on the floor

5

telephone

 [countable] an act of secretly listening to someone's telephone, using electronic equipment:

The police had put a tap on his phone line.

6

barrel

 [countable] a specially shaped object used for letting liquid out of a barrel, especially beer

7

tune

 taps

 [plural] a song or tune played on the bugle at night in an army camp, and at military funerals

Definition from the Longman Dictionary of Contemporary English
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