• Webster's Revised Unabridged Dictionary
    • n Elbowboard The base of a window casing, on which the elbows may rest.
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Century Dictionary and Cyclopedia
    • n elbowboard The board at the bottom of a window which forms the inner sill.
    • n elbowboard In psychology, an apparatus for determining the just noticeable (passive) motion of the forearm, that is. the just noticeable change of articular sensation at the elbow. Also called arm-board. The forearm and hand (palm down) are laid upon the hinged board, which is thus brought to the horizontal: the elbow-joint rests directly above the hinge. The experimenter then gently draws down the weight, and thus raises the forward end of the board. The observer reports the first indication of articular sensation at the elbow.
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