To Knock (or beat) the tar out of
To Knock (or beat) the tar out of : Phrases
To beat, whip, or belabor without mercy.
Jack didn't have a good first soccer game - he tried to knock the tar out of the ball instead of learning to kick it with his feet.
The expression may have been brought to this country by some Scottish or north-of-England sheepherder who may have used it in a literal sense. Many centuries ago it was learned that a sore on a sheep, as from an accidental cut in shearing, could be protected against the festering bites of flies if smeared with tar. However, when tar once gets embedded into a sheep's wool, its removal is difficult. Thus, used in a literal sense, to beat a sheep's side for the removal of tar. Thanks to Katie Cutie.
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