zero-bomb 

On Newgrounds - to rate a flash or audio piece 0/5 for the sole purpose of bringing down the rating of that piece of work, for the sole purpose of annoying the author.

Elsewhere - to rate a piece of work the lowest possible grade for the same purpose. (Also called 1-bomb where the lowest rating is 1, but not commonly used outside of Newgrounds.)

Considered a form of spam.

<gnuwtey> Aw man, my flash's rating went from 4.04 to 2.85 with only 6 votes. Stupid zero-bombers.
<dernston> I agree, those zero-bombers really are annoying.

zero-bomb by Mr. Briggs October 16, 2009

Zero Bomber 

Someone who votes zero on submissions (on websites that use a 0-5/0-10 voting system generally) for no reason/or due to hate and not actually judging on the submission, in target to lower the score of it.

Dammit, now I'll never get on the top rated list due to that damn zero bomber!

Zero Bomber by Smitfraud February 25, 2012