Definition of eviler:
(adj) :
Intending to harm; malevolent.
(adj) :
Morally corrupt.
(n) :
Moral badness; wickedness; malevolence; the forces or behaviors that are the opposite or enemy of good.
(adj) :
Producing or threatening sorrow, distress, injury, or calamity; unpropitious; calamitous.
(n) :
Something which impairs the happiness of a being or deprives a being of any good; something which causes suffering of any kind to sentient beings; harm; injury; mischief.
(adj) :
(computing, programming, slang) Undesirable; harmful; bad practice.