To place or put something into a pocket; to pocket something by putting it into one's clothing.
From em- (in) + pocket (small bag or pouch). Pocket comes from Old French poche, ultimately from Germanic sources, and emerged as clothing pouches became standard.
Empocket is basically a fancy Elizabethan way to say 'steal discreetly'—when pickpockets or courtiers would 'empocket' valuables, the prefix 'em-' made it sound like the object was being placed into a condition or state of being pocketed, suggesting deliberate criminal action.
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