Something that opposes or counters a predetermined outcome; a factor that works against predetermined fate or fixed results.
From anti- + predeterminant (something that determines in advance). Predeterminant comes from pre- (before) + determinant (deciding factor). This is a rare philosophical or technical term.
In biology, genes might be predeterminants of traits, but environment acts as an antipredeterminant—nature versus nurture is basically predetermined factors versus antipredeterminants!
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