deathwatch beetle, (Xestobium rufovillosum), an anobiid, or borer insect, of the family Anobiidae (insect order Coleoptera) that makes a ticking or clicking sound by bumping its head or jaws against the sides of the tunnels as it bores in old furniture and wood. According to superstition, the sound, actually a mating call, was believed to forecast an approaching death. Its name is derived from the credence that it was often heard by the people “on watch” with an ill person on the verge of death. These beetles tend to be small (1 to 9 mm, or less than 1/2 inch) and cylindrical. When disturbed, they usually pull in their legs and play dead.