Jam, v. t. [imp. & p. p.Jammed (jămd); p. pr. & vb. n.Jamming.] [Either fr. jamb, as if squeezed between jambs, or more likely from the same source as champ See Champ.]
1. To press into a close or tight position; to crowd; to squeeze; to wedge in.
The ship... jammed in between two rocks. De Foe.
2. To crush or bruise; as, to jam a finger in the crack of a door.
3. (Naut.) To bring (a vessel) so close to the wind that half her upper sails are laid aback. W. C. Russell.