circular error

American  

noun

1. Horology. loss of isochronism in a pendulum moving through circular arcs of different sizes: sometimes avoided by causing the pendulum to move through cycloidal arcs.

2. Military. error measured as the distance from the center of a target to the point of impact of a bomb or shell, or to the ground zero of an aerial burst.

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Etymology

Origin of circular error

First recorded in 1880–85

Example Sentences

A strike is considered accurate if it lands within a "circular error probable," usually 10 meters around the object being targeted.

From Salon

A March 2006 report by the US Center for Non-proliferation Studies, concluded it had a "circular error probable" of 2km to 4km, meaning that half the missiles fired would fall outside a circle of that radius.

From BBC

The system will double the accuracy, or halve the "circular error probability," of each of the 1,650 Minuteman warheads.

From Time Magazine Archive

REDSTONE: Circular error probability, target systems, pipeline requirements, deterrent gaps . . . counterinsurgency . . . soft target .

From Time Magazine Archive

The second part represents the addition necessary if the swing is circular and not cycloidal, and therefore expresses the “circular error.”

From Project Gutenberg