What does li'l mean? Li'l is an abbreviation of the word little. It's often used in names or titles to emphasize youth or physical size.

Lil is for long LITTLE, most of those rappers who called themselves Lil do so when they started rapping at a very young age, when they turned adults it becomes very hard to change their names because the Lil name has been known as their stage names.

Lil is a quaint little feminine name not to be mistaken for small personality. A shorthand of Lily, from the Latin lilium, Lil means "lily flower," though many believe it also reflects "purity." Across cultures, the lily flower is an enduring symbol, embodying passion, innocence, and fertility.

The form lil is used, but the most common variant seems to be lil' (capitalized when it is a name). Wikipedia. "Lil" is a kind of prefix and is the short form of "little". It is often spelled with an apostrophe as "Lil'" or "Li'l".