Doppelgaga 

A person who is accused of copying Lady Gaga, whether it be through fashion-sense, music, or mannerisms. It comes from the word Doppelganger, "A word that has come to refer to any double or look-alike of a person," and the word Gaga.

Person A - Did you see Nicki Minaj at the 2011 VMAs?
Person B - Yeah, she was such a Doppelgaga in that outfit.

Doppelgaga by Anitram R September 28, 2011

doppelgagger 

noun: like a doppelganger, a double, or look-a-like. but the less attractive version.

can also be used to describe the less attractive of siblings that resemble each other.

i saw someone who looked just like an ugly version of you.

eric roberts is julia robert's doppelgagger.

dennis quaid is randy quaid's doppelgagger.

joaquin phoenix is all the other phoenix's doppelgagger.

doppelgagger by mugwai64 November 8, 2011

Doppelgagger 

The person who repeats a just-told joke or gag and expects the same laughs.

"Fred just told that joke so it's not going to be as funny just because you told it, you Doppelgagger!"

Doppelgagger by ToadStool August 9, 2012