Origin: bef. 900; OE spring and spryng

The sense of the season of the year after winter (when plants spring up) is first recorded in springtime (before 1398, in Trevisa’s translation of Bartholomew’s De Proprietatibus Rerum), but is found in the form spring in 1547, possibly as a shortening of the earlier spring of the leaf (1538).

Chambers Dictionary of Etymology
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