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jack (n.)

Old form(s): iacke

figure of a man who strikes a bell on the outside of a clock

R2 V.v.60	[Richard alone, of Bolingbroke] I stand fooling here, his jack of the clock
R3 IV.ii.113	[King Richard to Buckingham] like a Jack thou keep'st the stroke / Betwixt thy begging and my meditation