Extensible partial automorphism

Symbol-free definition
A partial automorphism of a group is said to be extensible if it is a partial automorphism for any bigger group containing that group. In other words, for any bigger group containing the group, the given partial function can be realized as the restriction of an automorphism on the bigger group.

Stronger properties

 * Partial inner automorphism
 * Partial extensible automorphism: Any partial automorphism obtained by restricting an extensible automorphism, is an extensible partial automorphism