"bush mug" is a term coming from tumblr originating from blog user psyducker.
it started when this user posted the sentence "if you send me continue to send me asks even if i ignore then you’re a"--

**picture of a bush**
**picture of a coffee mug**

this post sparked much confusion and irritation among every single tumblr user who has anything to say about it. notes overflowing with "i've been staring at this for 43 minutes and do not understand" and "leaf cup? bush cup? moss mug? i do not understand" and "i've been seeing this goddamn fucking post all over my dash and still no not under stand what the fuck it's supposed to mean"

the meaning has evolved from whatever the originally intended meaning was, and now it is meant to be entirely ambiguous and is mostly used for humorous affect because nobody really has any idea what you're calling them. it might be a compliment but it might be an insult and so you're left to just stand there like "wha?? a bush... mug? i'm sorry???" someone familiar with the term would understand that it is meant to be ambiguous and you're not supposed to know, so they may reply in calling you something like a "shrubbery cup."
A: hey, i been checking out your new haircut. you kinda look like a bush mug now.
B: what?
A: i said you're looking like a bush mug.
B: is that good?
A: it's like a shrubbery cup.
B: what are you talking about?
A: ugh, you're such a leafy goblet.

C: y'know you're kinda a bush mug.
D: well you're a fucking shrubbery cup so go shit yourself.
C: hey buddy, i meant no harm. i meant bush cup as in a moss beaker.
D: ohh why didn't you say so?!

E: heh heh... you're a bush mug...
F: imma pop you you fucking twat
by The Joking Quace of Sparts September 7, 2013
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