2a v. — Aboriginal, especially Western Canada
to cleanse one's spirit by fanning ceremonial smoke over oneself or someone else.
Type: 4. Culturally Significant — Smudging is a cleansing ceremony traditional to many Aboriginal communities. The term smudge in the context of ceremonies is most frequent in Canada (see Chart 1). The term is most prevalent in Western Canada, yet the practice is country-wide, perhaps even continent-wide (see Chart 2, where Saskatchewan, British Columbia and Quebec show the highest frequencies within Canada).
The ritual involves burning one or several materials, and then fanning the smoke over oneself to clear the air, mind and spirit. Sweetgrass, cedar, sage and tobacco are most commonly used in First Nations' ceremonies (see Canadian Encyclopedia reference). While practices vary, smudging is considered to be a way of driving away negative energies (see Mullin et al. 2001). The cleansing ritual entails an initial "washing" of hands with smoke, followed by covering the entire head and body with smoke (see Gov't. of Manitoba reference).
2b n. & adj. — Aboriginal, especially Western Canada
a spiritual cleansing ceremony using the smoke from a variety of materials.
Type: 4. Culturally Significant — The term smudge is used interchangeably with smudging. Both smudge and smudging are also used attributively as modifiers preceding "ceremony" (see the 2000, 2001 quotations). See the 2014 quotation for the particular herbs used.
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Chart 1: Internet Domain Search, 20 Apr. 2016
Chart 2: Regional Domain Search, 4 Mar. 2015