In archery, arrows have three feathers (in a Y shape) rather than four (+) so that it can slide past the bow without damaging the feathers or the bow. This means that the arrow can be nocked either the right way (with the leg of the Y away from the bow) or the wrong way (with the leg of the Y towards the bow).
In medieval Europe, the arrow would be nocked with the bow held horizontally. To make it easier for archers to quickly and easily nock their arrows, the feather to go away from the bow (pointing upwards) was a different color, and came from a cock (rooster). So when drilling new archers, if they nocked the arrow the wrong way, the instructor would shout “Cock Up!”.
In archery, arrows have three feathers (in a Y shape) rather than four (+) so that it can slide past the bow without damaging the feathers or the bow. This means that the arrow can be nocked either the right way (with the leg of the Y away from the bow) or the wrong way (with the leg of the Y towards the bow).
In medieval Europe, the arrow would be nocked with the bow held horizontally. To make it easier for archers to quickly and easily nock their arrows, the feather to go away from the bow (pointing upwards) was a different color, and came from a cock (rooster). So when drilling new archers, if they nocked the arrow the wrong way, the instructor would shout “Cock Up!”.
This came to mean a mistake.
This is almost certainly not true.
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