A young child. A facetious formation from the Anglo-Saxon ci[l]d, a child. The l is often silent, as in calm, half, golf, etc. At one time fault was prononnced fauʹt.
“‘Are these your own kids?ʹ I inquired presently. ‘Yes, two of them: I have six, you know.ʹ”—H. A. Beers: Century Magazine, June, 1883, p. 282.