latch needle
Needle with a hooked end that is closed by means of a small articulated piece (the latch).
butt 
The raised part of the needle that allows it to move along a groove.
shank 
Part of the needle between the butt and the hook; it fits into a groove.
latch 
Articulated piece that closes the hook to hold the thread.
hook 
Curved part in which the thread is inserted.