What does "jam" mean?

Jam: To press into a close or tight position; to crowd; to squeeze; to wedge in. The . . . jammed in between two rocks. De Foe.

Additional senses

  1. 2.To crush or bruise; as, to jam a finger in the crack of a door. [Colloq.]
  2. 3.(Naut.) To bring (a vessel) so close to the wind that half her upper sails are laid aback. W. C. Russell.
  3. 4.A mass of people or objects crowded together; also, the pressure from a crowd; a crush; as, a jam in a street; a jam of logs in a river.
  4. 5.An injury caused by jamming. [Colloq.]
  5. 6.A preserve of fruit boiled with sugar and water; as, raspberry jam; currant jam; grape jam. Jam nut. See Check nut, under Check. -- Jam weld (Forging), a butt weld. See under Butt.

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