What is the definition of dating
There is little evidence to support the theory that the mark here is specifically that fixed by the Assay Office as the standard for gold and silver.
This expression, dating from the 14th century, originally meant to attain the rank of knight, since a newly dubbed knight was presented with a pair of gilt spurs as a symbol of his chivalry.
Paulding’s The Diverting History of John Bull and Brother Jonathan (1813)to scratch Meeting specified standards; acceptable, satisfactory.
The scratch of the expression was the line drawn on the ground in various sporting events: prize fighting, cockfighting, foot racing, and others.
Contestants who came “up to [the] scratch” were worthy competitors, ready to undertake the challenge and prove their mettle.
Thus the expression is similar in origin and current meaning to toe the mark.
The allusion is to the wing-shaped badges worn by pilots and other aircraft crew members upon completion of rigid requirements and strict training.