Yardstick

n. criterion, standard of measurement; yard-long measuring stick (about 0.91 meters long)

A yardstick is a tool used to physically measure lengths of up to three feet (a yard/0.9144 metres). Most yardsticks are flat wooden boards with black markings at regular intervals and metal tips. Many new yardsticks have imperial units markings on one side (three feet with inch and fractional inch) and metric units on the other side (one meter with centimeter and millimeter).Yardsticks may be used as pointing devices for posters and projections.
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Noun
1. a measure or standard used for comparison; "on what kind of yardstick is he basing his judgment?"
(hypernym) standard, criterion, measure, touchstone
2. a ruler or tape that is three feet long
(synonym) yard measure
(hypernym) rule, ruler

(n.)
A stick three feet, or a yard, in length, used as a measure of cloth, etc.
  

same as benchmark.