Yes they do have bristles. They have three main places where they are at.In the Thorax the Abdomen And the Exopodite.
The Germans made it up. It means "editable crustacean"
crayfish : early 14c., crevis, from O.Fr. crevice "crayfish" (13c., Mod.Fr. écrevisse), probably from Frankish *krebitja or a similar Germanic word that is a dim. form of the root of crab (1); e.g....
They use them to clean
its a crawfish
Crayfishing in Armenia
Crawfish Farming