ladder
nounAn often portable structure consisting of two long sides crossed by parallel rungs, used to climb up and down.
nounSomething that resembles this device, especially a run in a stocking.
nounA means of moving higher or lower, as in a hierarchy.
nounA series of ranked stages or levels.
nounA fish ladder.
nounAn athletic workout in which one does progressively longer intervals followed by progressively shorter intervals.
nounOne of the intervals in such a workout.