Halogen Abstraction Definition:

In radical reactions, a type of arrow-pushing pattern in which a halogen atom is abstracted by a radical, generating a new radical.

Halogen Abstraction Explained:

Halogenation is a process where hydrogen in an organic compound is replaced by halogens and one of the ways it does that is through radical reactions. In this reaction in particular the Hydrogen atom itself transfers to the other side, making a new radical.