Why is the ninth month called September?
device for fastening, c.1300, probably from clamb, perhaps originally past tense of climb (v.), or from Middle Dutch clampe (Dutch klamp), from West Germanic *klamp- "clamp, cleat;" cf. Middle Low German klampe "clasp, hook," Old High German klampfer "clip, clamp;" also probably related to Middle Dutch klamme "a clamp, hook, grapple," Danish klamme "a clamp, cramp," Old English clamm "fetter;" see clam (n.).
"to fasten with a clamp," 1670s, from clamp (n.). Related: Clamped; clamping.
An instrument for the compression or grasping of a structure.