pirl

The verb is from the 16th century. Origin uncertain; related to purl, pirn, prill (OED; more at pern, preen). The noun was derived from the verb in the 19th century.

pirl (third-person singular simple present pirls, present participle pirling, simple past and past participle pirled)

1. (transitive) To twist or wind, especially into a cord or braid etc.
2. (intransitive) To ripple or swirl, especially of water.
3. (transitive) To cause to revolve or spin.

pirl (plural pirls)

1. A ripple; a twist or curl.