"Friends with benefits" entered into our collective sexual lexicon years ago, but it's a slippery term. If you're dying to delineate your fuzzy relationship status even further, researchers at Arizona State University and Northern Illinois University have broken down FWBs into seven different categories in a study published in the latest issue of the Journal of Sex Research. Now you can add even more letters to your relationship acronym!

True Friends (what we call TF)

Academic Definition: An important friend considered a safe sexual partner.

Translation: You actually want to hang out with him with your clothes on.

Just Sex (JS)

Academic Definition: Other than sexual encounters, little interaction occurs.

Translation: You only talk to him after 11 p.m.

Network Opportunism (NO)

Academic Definition: Friends whose shared network allows them to interact, typically while consuming alcohol.

Translation: He's your end-of-the-party default option.

Successful Transition (ST)

Academic Definition: Intentionally and effectively using an FWB to initiate a romantic relationship.

Translation: Through your wit and charm, you've turned it into a real thing.

Unintentional Transition (UT)

Academic Definition: An FWB leads to a romantic relationship, although it was not the original intent.

Translation: Whoops! He's your accidental boyfriend.

Failed Transition (FT)

Academic Definition: One or both partners attempted, unsuccessfully, to generate a romantic transition.

Translation: You're heartbroken (or he is)... And now you're having heartbreak sex.

Transition Out (TO)

Academic Definition: Sexual interactions between partners from a terminated romantic relationship.

Translation: Your halfhearted breakup sex lasts for months.

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