Definition of wellhole 

1 : the hole, pit, or shaft of a well

2a : the open space in a floor or through a series of floors for the accommodation of a staircase

b : the open space about which the stairs of a winding or circular staircase turn

3 : a cavity for movement of a counterbalance or similar mechanical device

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First Known Use of wellhole

1663, in the meaning defined at sense 2a

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The first known use of wellhole was in 1663

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exaggeratedly or childishly emotional

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