Origin: 1375–1425; late Middle English (north) < Scandinavian; compare Norwegian svirla; cognate with Dutch zwirrelen to whirl, German (dial.) schwirrlen to totter; all < a root *swir- (whence Danish svirre to whirl, German schwirren to whir) + -l- frequentative suffix
early 15c., "whirlpool, eddy," originally Scottish, perhaps related to dialectal Norw. svirla or Du. zwirrelen "to whirl." The meaning "whirling movement" is from 1818. The verb is attested from 1510s, with an isolated instance from 14c.