Henry has been getting erratic scores on his tests: 40% last week, but 98% this week.

The V-2's directional system was notoriously erratic. In May 1947, a V-2 launched from White Sands Proving Ground headed south instead of north, missing downtown Juarez, Mexico, by…

erratic conduct

During the last ice-age, massive stones were carried for miles by the scouring glaciers, only to be left, like passengers at the end of the line, when the glaciers retreated. Stran…

The term for a displaced boulder is an erratic, but in the nineteenth century the expression seemed to apply more often to the theories than to the rocks.