C-clamp
Portable tool with a C-shaped frame, used for keeping objects from moving while working on them.
handle 
Sliding bar for tightening or loosening the adjusting screw, thereby spreading or closing the jaws.
adjusting screw 
Threaded shank whose rotation is controlled by the handle; it moves the jaw toward or away from the piece to be clamped.
frame 
Rigid metal support in the shape of a C, having the fixed jaw on one end, while the other end contains a hole for the adjusting screw.
throat 
Opening made by the frame.
swivel head 
End of the tightening screw; it pivots to adjust to irregularly shaped objects.
movable jaw 
Smooth or striated jaw that presses an object against the fixed jaw.
fixed jaw 
Smooth or striated part against which the movable jaw presses an object.