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1.
Commonly mistaken as the word "unreal". Often used to describe a remarkable feat or a boneheaded play. Other words related to this that are often confused; onbelievable (unbelievable), ondo (undo), ontarp (untarp), onenthusiastic (unenthusiastic), onused (unused), onhittable (unhittable)
"We suck, this is the worst team i've ever seen, we can't make a single play in the field! this is onreal"
by chapelleshow April 28, 2009
 
2.
Originally a mispronunciation of unreal, but has become a word in it's own right due to the vowel's ability to be emphasized.
" Did you see that chick? She was totally onreal!" (ONNNreal)
by Spiketronic May 02, 2013