a. 1. Moving by jerks and starts; characterized by abrupt transitions; as, a jerky vehicle; a jerky style. [ 1913 Webster ]
2. Foolish; ridiculous; stupid. [ slang ] [ PJC ]
n. [ Corrupted from Peruv. charqui dried beef. ] Meat, especially beef, that has been cut in strips and dried; meat that has been jerked; see first jerk, v.; as, beef jerky [ PJC ]