rimmer1
/ˈrɪmə/Chiefly US
noun
A tool for enlarging holes; = reamer.
Origin
Early 19th century. Either from rim + -er, or perhaps a variant of reamer.
rimmer2
/ˈrɪmə/noun
A tool or machine for making or ornamenting the rim of a pie, pastry, etc. Frequently with preceding word, especially as pie rimmer.
Origin
Mid 19th century; earliest use found in U.S. Patents. From rim + -er.