A man who drinks protein milkshakes way more than he actually works out, to build what looks like strong muscles, but is actually the work of milkshakes. This gives them the illusion that they are tough ....however the reality is very different.
Person 1 - man look over there at that tough looking guy, his pecs are huge! he must bench press for a day job!
Person 2 - nah he's a milkshake marine, he lifts more shakes than he does weights...

See : Douchebag, Show Pony.
by HIV69 November 14, 2012
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