The feeling of jealousy and betrayal you get when you catch/find a colleague or other drinking from a mug that is specifically yours, that you always drink from and is always on your work desk, without your permission. Such an event tends to happen when you are away from the mug and people think you're not looking, won't notice, won't catch them or when you have gone out and the individual thinks they'll be finished with it in time before you get back, but you get back early and catch them. Mug envy can happen when someone steals your mug intentionally or accidentally.
*Jane finishes her hot drink, washes it up and leaves the office to go out*

Carl (To himself): "There's no standard mugs left here, just Jane's... I'll use that - she's gone out and I'll be finished before she gets back"

*Jane re-enters* "Silly me, forgot my diary... Oh, um, Carl - is that my mug you're drinking from?"

Carl: "Oh, yeah - I didn't think you'd be back so soon and yours is the only mug I can find to drink from"

Jand "Wow, mug envy much".
by OfficeNewb November 16, 2013
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