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late 14c., "a going around; a line going around," from Old French circuit (14c.) "a circuit; a journey (around something)," from Latin circuitus "a going around," from stem of circuire, circumire "go around," from circum "round" (see circum-) + ire "to go" (see ion). Electrical sense is from 1746. Of judicial assignments, from 1570s; of venues for itinerant entertainers, from 1834. Circuit breaker is recorded from 1874. Related: Circuital.
"to go around," early 15c., from circuit (n.). Related: Circuited; circuiting.
The term is used loosely for any device or subsystem using electrical or electronic components. E.g. "That lightning bolt fried the circuits in my GPS receiver". An integrated circuit (IC) contains components built on a Silicon die.
the apparent diurnal revolution of the sun round the earth (Ps. 19:6), and the changes of the wind (Eccl. 1:6). In Job 22:14, "in the circuit of heaven" (R.V. marg., "on the vault of heaven") means the "arch of heaven," which seems to be bent over our heads.