To "hook-up" with the same individual repeatedly, with out actually going out together "officially".
Meeting up, hanging out, & engaging in sexual activety with a specific individual on a regular basis.. But never claiming to be dating, or speaking about what it is that you are doing at all. (Usually begins at bars or other group social functions.)
Also known as "common law dating".
Becki & John? Oh, they're not officially together.. They are just San Jose dating.