Wiktionary
vb. To contribute toward a group effort.
Usage examples of "pull an oar".
He could knot and splice, hand, reef, and steer, cast the lead or pull an oar, all of them far better than his captain.
Those had only one bank of oarsmen with the rest of the space in the narrow hulls given over to cargo and soldiers who hadn't been trained to pull an oar--another kind of cargo so far as the sailors were concerned.
In his place is coming a class of men miscalled sailors, who never reefed a sail or coiled a cable, who do not know how to launch a life-boat or pull an oar, and in whose career we meet the ridiculous episode of the life-boats of the Titanic, where women were obliged to take the oars from their hands and row the boats.
Few of the Defenders could be of any use at these skilled tasks, but by now they could all pull an oar, more or less, and they and the Marines were sent off to complete the ship's water at a spring a little way up the river.