Sentence:  Often <WSD>omegas</WSD> go into heat and release pheromones that drive alphas wild. 
Meaning of the word marked with <WSD> tags:  In omegaverse fan fiction, a person of a sexually-submissive (and sometimes secondary) gender/sex that is driven by biology, magic, or other means to bond with an alpha, with males of this type often being able to get pregnant.