Deins is a Filipino slang word coming from the Filipino phrase "hindi naman". English equivalents would be "hell no" or "no way" although these are only equivalent in the sentiment of use and not the literal
translation as there is no specific English
translation for "naman".
Dein (without the s) is also used in the same context.
It is believed to have
originated in the South of Metro Manila, specifically the Alabang region, but is coming into wide usage all over Metro Manila.