Quick Definition: To complete a pick up by getting a girl to give you her phone number.
A number close is what AFCs or non-PUAs consider as a regular “pickup” in the mainstream dating scene. As PUAs we know better and, thus, like to differentiate between different kinds of closes (kiss close, number close, fuck close, etc.). These terms originate from sales terminology—”close a deal”—and also the sales lead cycle—opening, interest, leading, exploration, expectations, closing, implementation, follow-up.
Essentially, a number represents a “lead” and is your communication tool to further your relationship with the girl.
I #closed an HB8 brunette at the mall today.