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mouchette

[moo-shet]
noun Architecture.
  1. a daggerlike form, especially in tracery, created by a segmental and an ogee curve so that it is pointed at one end and circular at the other.

Origin of mouchette

1925–30; < French: orig., the fillet below an ovolo, projecting part of a cornice; hence, with the common sense “what protrudes,” probably derivative of moucher to cut or knock off (something protruding) (see -ette), apparently extended sense of moucher to wipe (a person's) nose < Vulgar Latin *muccāre, derivative of Latin muccus, mūcus mucus
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018