tuwerka

Etymology
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Noun

 * 1) nut, fastener
 * 2) rivet
 * 3) screw, bolt

Etymology
.

Noun

 * 1) a nut; a fastener: a piece of metal, usually square or hexagonal in shape, with a hole through it having machined internal threads, intended to be screwed onto a bolt or other threaded shaft

Etymology
.

Noun

 * 1)  nut