Definition of "diss"

diss¹

/dɪs/

verb
third-person singular simple present disses, present participle dissing, simple past and past participle dissed
1. (slang) To put (someone) down, or show disrespect by the use of insulting language or dismissive behaviour.
  Quotations
  When a journalistic rival tries to "dis" youAnd to prejudice you in the public's eyes.Don't stigmatise his charges as a "tissueOf palpable, unmitigated lies."
  1905, 10 December, The Sunday Times (Perth), "A New Word", page 4
noun
plural disses
1. (slang) An insult or put-down; an expression of disrespect.

/dɪs/

/dɪs/