Sel3a is a North African Arabic slang word that has made its way into French rap, particularly from artists like Soolking who have Algerian roots. It literally means "merchandise" or "goods".
However, in the context of this song and much of French street slang, "sel3a" often refers to illicit goods, particularly drugs. It can also be used more broadly to refer to something valuable or desirable, sometimes even a person, but its primary connotation in this song is likely related to illegal substances, given the context of
"Sel3a" is a fast, confident track from Soolking's album Sans visa, featuring Marseille rapper Naps. The lyrics paint a night out: a few drinks, a Vuitton bag, a fast GT3, and a woman he calls "sel3a" - Algerian slang for someone so attractive she's basically a catch. He plays it cool, tells her he loves her, and she believes him.
Between the boasting are glimpses of home: Oran, Marrakech, listening to the rai legend Cheb Hasni, and feeling unstoppable like a Ligue 1 player. The song closes in Algerian Arabic, with lines about Algeria and being crazy in love ("na3cha9 bik"), tying the swagger back to where Soolking and Naps come from.