What is the meaning of Diss?

To put (someone) down, or show disrespect by the use of insulting language or dismissive behaviour.

An insult or put-down; an expression of disrespect.

Dissertation.

Ampelodesmos mauritanicus syn. Ampelodesmos tenax, a reedy grass used for cordage.

to diss (to show disrespect)

a diss

diss (insult or put-down)

diss, rejection

D-sharp; the note D♯

Source: wiktionary.org