Green’s Dictionary of Slang

1. an act of disparagement or of disrespect [the earlier UK use seems to have faded before its resurrection by US blacks in the 1980s].

1923		J. Manchon Le Slang.
1987		Boogie Down Prods ‘Criminal Minded’ 🎵 Some MCs on the mike are frauds / Saying styles like this to create a dis.
1989		J. Doyle College Sl. Dict. 🌐 dis [CMU] insult.
1991		L. Bing Do or Die (1992) 31: As far as gangbangin’ goes, I’d mop her up if she come to me with some dis’ and like that.
2000		Other Side of the Wall: Prisoner’s Dict. July 🌐 Dis: Disrespect.
2005		L. Theroux Call of the Weird (2006) 192: It contained a dis of the one Jackson rapper to make it internationally.
2016		F. Stuart ‘Dispatches from the Rap Wars’ in chicagomag.com 🌐 Then there’s an in-between kind [of video], which to an outsider sounds like generic disses but is actually very targeted, with the rapper flashing a rival gang’s hand signs upside down.
2018		I. Welsh Dead Man’s Trousers [26]: [T]hat isnae meant as any diss oan the cat.

2. a disappointment.

1989

P. Munro Sl. U. 69: That C- on my paper was total dis.