tolerator - v.tr.
1 allow the existence or occurrence of without authoritative interference.
2 leave unmolested.
3 endure or permit, esp. with forbearance.
4 sustain or endure (suffering etc.).
5 be capable of continued subjection to (a drug, radiation, etc.) without harm.
6 find or treat as endurable.

tolerator n. [L tolerare tolerat- endure]