n.1 a person who does not know or is not known in a particular place or company.
2 (often foll. by to) a person one does not know (was a complete stranger to me).
3 (foll. by to) a person entirely unaccustomed to (a feeling, experience, etc.) (no stranger to controversy).
4 a floating tea-leaf etc. held to foretell the arrival of a visitor.
5 Parl. a person who is not a member or official of the House of Commons.
Etymology: ME f. OF estrangier ult. f. L (as STRANGE)