Tertiary Alkyl Halide Definition:

An organohalide in which the alpha (a) position is connected to three alkyl groups.

Tertiary Alkyl Halide Explained:

Classified as primary, secondary, or tertiary according to how they are substituted at the carbon where the halogen is attached. In a main alkyl halide, the carbon that bears the halogen is directly attached to one other carbon, in a secondary alkyl halide to two, and in a tertiary, to three.