One of the mysteries of the English language finally explained.
A repeated crackling sound.
Mid 17th century; earliest use found in Nathaniel Whiting (d. 1682), satirist and nonconformist minister. Apparently a reduplication (with vowel variation) of crackle, perhaps with imitative motivation, the higher vowel being intended to convey a sharper cracking sound; compare crick-crack, and also crickling, crickle, crick.
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