a portable balance with two unequal arms, the longer one having a movable counterpoise and the shorter one bearing a hook or the like for holding the object to be weighed.
a portable balance consisting of a pivoted bar with two unequal arms. The load is suspended from the shorter one and the bar is returned to the horizontal by adding weights to the longer one
[C17: from steel + yard1 (in the archaic sense: a rod or pole)]