1815, "to say bad words, use profane language," a vulgar pronunciation of curse (v.). The transitive sense of "to curse, swear at" is by 1838. Related: Cussed; cussing. To cuss (someone) out is attested by 1881.
The loss of -r- before -s- is not uncommon: Compare arse/ass (n.2), burst/bust, horse/hoss, barse/bass, garsh/gash, parcel/passel.
updated on October 04, 2022