Cohabidating is an arrangement whereby two people decide to live together on a longterm or permanent basis in an emotionally and/or sexually intimate relationship. The term is most frequently applied to couples who are not married. Such an arrangement often comes to be when both parties have succumbed to the social pressures to "move their relationship to the next level". This may also be followed by the purchase of a puppy a.k.a. test child and a joint checking account.
Hey, did you hear that John and Kim are cohabidating? Kim's mom is pretty old-fashioned, so she's not hot on her daughter living with her boyfriend before they decided to get hitched.