- any of various small terrestrial isopods, especially of the genera Armadillidium and Oniscus, which can roll themselves up into a spherical shape.
Origin of pill bug
An Americanism dating back to 1835–45
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for pill bug
It looks like some sort of pill-bug half an inch long, doesn't it?The Animal World, A Book of Natural History
- any of various woodlice of the genera Armadillidium and Oniscus, capable of rolling up into a ball when disturbed