The word "retainer" used in rap vernacular often is referring to keeping a thug on hand that is willing to do dirt. The celebrity retains this person's services thru cash payment, or other bartering options such as weed or pussy in the event that a punch needs to be thrown (or otherwise) and the celebrity would be open to a potential costly lawsuit, whereas the retainer does not have enough money worth be sued for, etc.
When Charlemagne Tha God was instigating Nelly during an interview, he was warned "Hey,man...just say what you wanna say. We're all men. I keep retainers just for guys like you".
I little piece of plastic and metal that sits in your mouthafter the removal of Braces. Can easily get lost for they are often translucent, and are highly enjoyed by dogs as a tasty snack.
If you were going to apply for a job (most job managers don't want peirced employees.), and you have a nose piercing, you could use a piercing retainer in the place of your nose ring... not to noticable, unless close in each others face.
When a male has multiple females ready to talk, hang out with, but most importantly... fuck. Usually this phrase will be used when a guy is successfully playing the field and scoring a lot of bitches snapchats from the bars.
1) Someone who gives a blowjob while still having his or her retainer in.
2) A preteen who engages in early sex because preteens are notorious for having braces.
Jeff is such a Retainer Banger I got a blowjob with plastic.