any of approximately 90 species of beetles (insect order Coleoptera) that range in colour from reddish brown to black and in size from 1 to 7 mm (up to 0.3 inch). The larvae bore through seasoned wood, reducing it to a dry powder. They do not enter varnished, painted, or treated wood. Powderpost beetle holes are often erroneously considered to be evidence of the antiquity of a wooden object.