It's what it do, in the Lou', ice grill, country grammar

from Nelly (Ft. Ali, Brandi, Gipp, Jermaine Dupri & Paul Wall) – Grillz Lyrics on Rap Genius

Meaning

Ali is a member of the St. Lunatics, Nelly’s crew from St. Louis and with grillz is how they roll.

Country Grammer refers to the Nelly album as well as their southern drawl:

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