1. (n.) A round; a step of a ladder; a rung.

2. (n.) A ball.

3. (n.) Something which rotates about an axis, as a wheel, or the drum of a capstan.

4. (n.) One of the pins or trundles of a lantern wheel.

adolescent stream arroyo beck bourn braided stream branch brook brooklet burn carousel channel creek crick disk doorstep flowing stream fluviation footrest footstep fresh freshet gill kill lazy stream meandering stream merry-go-round midchannel midstream millstream moving road navigable river race racing stream rest riser river rivulet roller rolling stone rotator rotor round roundabout run rung runlet runnel scale sike spill stream spoke stair stave step step stool stepping-stone stream stream action streamlet string subterranean river top tread wadi watercourse waterway wheel whirlabout whirler whirligig