rut

Etymology 1

From Middle English rutte (noun) and rutten (verb), from Old French rut (“noise, roar, bellowing”), from Latin rugītus, from rugīre (“to roar”).

noun

1. (zoology) Sexual desire or oestrus of cattle, and various other mammals.
2. The noise made by deer during sexual excitement.
3. Roaring, as of waves breaking upon the shore; rote.
4. (fandom slang) In omegaverse fiction, the intense biological urge of an alpha to mate, typically triggered by proximity to an omega in heat.
   Proximity to an omega in heat can sometimes cause alphas go into rut, an aggressive need for sexual intercourse usually triggered by the scent of an omega in heat. 2017, Marianne Gunderson, "What is an omega?: Rewriting sex and gender in omegaverse fanfiction", thesis submitted to the University of Oslo, page 36
   All the characters in this story pressure Dean to help Castiel through his rut, and clearly consider Dean’s resistance to be immature and an overreaction. 2019, Tessa Barone, "Just Go Find Yourself a Nice Alpha: Gender and Consent in Supernatural Fandom's Alpha/Beta/Omega Universe", thesis submitted to Oregon State University, page 34
   Early in Wicked Game, Steve goes into his first-ever rut. 2019, Chris van der Vegt, "The Second Genders: Utopia and Dystopia in Stranger Things Omegaverse Fanfiction", thesis submitted to Utrecht University, page 23

verb

1. (intransitive) To be in the annual rut or mating season.
2. (intransitive) To have sexual intercourse.
3. (transitive, rare) To have sexual intercourse with.
   “Alfred,” Ragnar continued scathingly. “All he cares about is rutting girls, which is good![…]” 2004, Bernard Cornwell, The Last Kingdom

Etymology 2

Probably from Middle English route, from Middle French route (“road”), from Old French route. See also rutter.

noun

1. A furrow, groove, or track worn in the ground, as from the passage of many wheels along a road.
2. (figurative) A fixed routine, procedure, line of conduct, thought or feeling.
3. (figurative) A dull routine.
   Dull job, no interests, no dates. He's really in a rut.
   Some people might say my life is in a rut / I'm quite happy with what I got 1980, Paul Weller (lyrics and music), “Going Underground”, in Setting Sons, performed by The Jam

verb

1. (transitive) To make a furrow.