Lil Wayne Reveals Madi Cannon Engagement, Months After Split

Lil Wayne isn't just back together with Madi Cannon ... he's wifing her up!!!

The rapper announced Monday night that he and Madi are engaged ... a shocking development that comes just months after they split.

While making a video congratulating B.G. on his own engagement, Weezy revealed he put a ring on it, saying ... "Congratulations, bitch. And I'm marryin' this one. This is Madison. This is my fiancée."

The 44-year-old and the 23-year-old were all smiles as they sent B.G. their love ... even though their relationship wasn't always smooth sailing.

Earlier this year, Weezy shut down previous engagement rumors and actually announced they'd split, saying ... "had a beautiful thing going with an amazing person," but he didn't want to be a "burden."

But it looks like the lovebirds are now back together ... and better than ever.

No word on a potential wedding date.