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whip; lash; scourge
stick; cane; rod; pointer
「笞」 has another reading with different meanings.
昔は笞で打つ罰が行われていたそうだ。
Apparently punishment by whipping used to be practiced.
馬に笞を当てて走らせる場面が映画にある。
There's a scene in the movie where a horse is whipped into running.
笞の跡が残るほど厳しい仕置きだった。
It was a punishment severe enough to leave whip marks.