rimmer

from The Century Dictionary.

• Same as reamer, rimer.
• noun An implement used in impressing ornamental figures upon the margins of the paste or crust of pies, etc. It may have the nature either of a hand-stamp or of an embossed roller.
• noun An instrument used in rimming mackerel; a plow; a rimming-knife.

from the GNU version of the Collaborative International Dictionary of English.

• noun An implement for cutting, trimming, or ornamenting the rim of anything, as the edges of pies, etc.; also, a reamer.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun An implement for cutting, trimming, or ornamenting the rim of anything, as the edges of pies, etc.; also, a reamer.
• noun One who performs oral sex on the anus of his/her partner.
• noun A mixture of confections, spices, and/or salts applied to the rim of a beverage glass or mug.