chaperon

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A person, especially an older or married woman, who accompanies a young unmarried woman in public.
2. n. An older person who attends and supervises a social gathering for young people.
3. n. A guide or companion whose purpose is to ensure propriety or restrict activity: "to see and feel the rough edges of the society . . . without the filter of official chaperones” ( Philip Taubman).
4. v. To act as chaperon to or for. See Synonyms at accompany.

Century Dictionary and Cyclopedia

1. n. A hood: a name given to hoods of various shapes at different times.
2. n. Specifically A hood or cap worn by the Knights of the Garter when in full dress.
3. n. A small shield containing crests, initials, etc., formerly placed on the foreheads of horses which drew the hearse in pompous funerals. Also written chaperonne.
4. n. Formerly, one who attended a lady to public places as a guide or protector; a duenna; now, more especially, a married woman who, in accordance with the rules of etiquette, accompanies a young unmarried woman to public places or social entertainments.
5. n. In entomology, the clypeus of the head of an insect; the part which supports the labrum or upper lip; the nasus; the epistoma.
6. To attend (an unmarried girl or woman) in public: said of an older woman or a married woman.
7. n. A conductor or guide; escort. Compare def. 4.

Wiktionary

1. n. An adult who accompanies or supervises one or more young, unmarried men or women during social occasions, usually with the specific intent of preventing some types of social or sexual interactions or illegal behavior.
2. v. to accompany, to escort
3. v. to mother

GNU Webster's 1913

1. n. A hood; especially, an ornamental or an official hood.
2. n. A device placed on the foreheads of horses which draw the hearse in pompous funerals.
3. n. A matron who accompanies a young lady in public, for propriety, or as a guide and protector.
4. v. To attend in public places as a guide and protector; to matronize.

WordNet 3.0

1. v. accompany as a chaperone
2. n. one who accompanies and supervises a young woman or gatherings of young people