A Word That Means “An assumption without fact”?

Question by C.J.: A Word That Means “An assumption without fact”?
I am looking for a word that goes with this definition; “A assumption without fact”, “When someone assumes without fact”.

I knew this word before but I forgot and have use Google a number of times with no luck.

Thanks!
I could not find it there, thanks though!

Best answer:

Answer by ﺕ SB22 ټ
Try thesaurus.com, Here, lets try it now:
http://thesaurus.com/browse/assumption

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