beat

noun

1
the act of beating to windward; sailing as close as possible to the direction from which the wind is blowing
2
a stroke or blow
the signal was two beats on the steam pipe
3
a regular rate of repetition
the cox raised the beat
4
the basic rhythmic unit in a piece of music
the piece has a fast rhythm
the conductor set the beat
5
(prosody) the accent in a metrical foot of verse
6
the sound of stroke or blow
he heard the beat of a drum
7
the rhythmic contraction and expansion of the arteries with each beat of the heart
he could feel the beat of her heart
8
a regular route for a sentry or policeman
in the old days a policeman walked a beat and knew all his people by name
9
a member of the beat generation; a nonconformist in dress and behavior
10
a single pulsation of an oscillation produced by adding two waves of different frequencies; has a frequency equal to the difference between the two oscillations

1
wear out completely
This kind of work exhausts me
I'm beat
2
be a mystery or bewildering to
This beats me!
Got me--I don't know the answer!

Also useful for “beat”:Unscrambler— Turn loose letters into real words