oldcomer

Meanings

1. An immigrant or the descendant of immigrants who has lived in their new environment long enough to become well-established.
2. One who has been acquainted with something for a long time; an established member of a group who is familiar with the group culture and resources.
3. A member of a therapeutic community who has achieved a trusted status and is assigned as a mentor to a newcomer.

Etymology

Blend of old + newcomer.