normalizer

Noun

 * 1) One who or that which normalizes, fits to a norm or standard etc.
 * 2)  The subset of elements of some group which leave some given subset invariant when conjugating it.
 * In symbols, the normalizer of some subset $$S$$ of group $$G$$ is the subset $$N(S) = \{g \in G | g^{-1}S g = S\}$$, so that $$S$$ would be a normal subgroup if $$N(S)$$ were the whole group.

Translations

 * German: Normalisator