Describes someone who is native to New Jersey but now living in a different part of the country, but trying to seem cool and hip by invoking Jersey-isms wherever possible.

the thing that you don’t have when you’re phones percentage is over 20

Term for a male aged 16-21 from Northern New Jersey who pretends to be a "city boy" from New York. A Jersey Boy is often of Italian descent and pretends to be "hard as shit" despite having in all probability grown up in an upper-middle class suburban neighborhood. Often Jersey Boys will smoke at least 2 packs of cigarettes a day, their only larger daily expenditure of money being on hair gel and ripped jeans. Often Jersey Boys will "talk shit about everything" despite "not knowing anything". The most common staples of a Jersey Boy's vocabulary include "fuck", "thats fucking bullshit", "what are you some kind of faggot", and "...me and the boys..." In defiance of biological fact, 99% of all Jersey Boys have black hair, and are often attracted to girls who most people would describe as either, in a good way, "freak(aaaaa)y" or in a bad way, "skanky". Most Jersey Boys will grow up to marry a woman they do not love, and have multiple kids who they will barely know, which suits their personalities as it will permit them to continue to "talk shit" long after their primes.

A kid who is not from new jersey, but has a speech impediment that sounds like a New Jersey accent.

An over the pants handjob.

A diss to a certain person who is acting gay.

Jersey boy is a nickname for a teenage boy in the 15-18 age range who plays hockey with his dad and also wears a matthews jersey. Hence the name jersey boy.