Définitions
1.AdjectiveAntagonistic to or causing deviations from that which is considered normal.
2.AdjectiveIn the opposite direction or position from what is normal or canonical.
3.AdjectivePerpendicular to a tangent of a curve or tangent plane of a surface but pointing opposite to convention.
4.NounA normal that points opposite to convention. For example, in solid geometry it is conventional for normals to point outwards, so an antinormal in solid geometry refers to a normal pointing inwards.