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definitions

flannelmouth

[flan-l-mouth]
noun, plural flan·nel·mouths [flan-l-mouth z] /ˈflæn lˌmaʊðz/.
  1. a person whose speech is thick, slow, or halting.
  2. a person whose speech is smoothly deceptive.

Origin of flannelmouth

An Americanism dating back to 1880–85; flannel + mouth
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018