n. — Newfoundland, Social customs
the practice of visiting houses in elaborate costumes and disguises and participating in various group activities during Christmas (see Image 1 at mummering
Type: 1. Origin — While janneying, mummering and mumming all describe the same practice popular in Newfoundland, the form janneying appears to be most used on the west coast of the Great Northern Peninsula (see Widdowson, in Halper & Story 1969: 217). In areas of Newfoundland where both the terms janneying and mummering are used, janneying is seen as the younger and less established term, and is sometimes used by older people to distinguish between folk play actors (who are always referred to as mummers and never as janneys) and younger disguised house-visitors.
In Cornish English, the term "jan" is a generic name for a Cornishman, so it is possible it was simply adopted in select regions of Newfoundland for 'mummers'. See also Widdowson in Story & Halpert (1969: 216-221).
See also COD-2, s.v. "janny", which is marked "Cdn (Nfld), ITP Nelson, s.v. "janny", which is marked "Newfoundland", DNE, s.v. "janny" and "jannying", and OED-3, s.v. "janney", which is marked "Newfoundland".