fu·​see fyü-ˈzē How to pronounce fusee (audio)
: a conical spirally grooved pulley in a timepiece from which a cord or chain unwinds onto a cylinder containing the mainspring and which by its increasing diameter compensates for the lessening power of the spring
: a red signal flare used especially for protecting stalled trains and trucks

Examples of fusee in a Sentence

Recent Examples on the Web Also visible through the caseback, is the fusee-and-chain transmission, an ultra-complex and very hard-to-make solution for providing a constant force escapement that was common during this brand’s namesake founder’s heyday. Paige Reddinger, Robb Report, 3 Sep. 2021

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'fusee.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


borrowed from French fusée "mass of thread around a spindle, explosive fuse, rocket, fusee in a timepiece," going back to Old French fusee "mass of thread around a spindle," from fus "spindle" (going back to Latin fūsus, of obscure origin) + -ee, suffix of association or containment, going back to Late Latin -āta (going back to Latin, feminine of -ātus -ate entry 3)

Note: In the later Middle Ages, French fusée designated a kind of rudimentary gunpowder-filled projectile, apparently resembling thread wound around a spindle—hence the later application to fuses, fireworks, etc.

First Known Use

1622, in the meaning defined at sense 1

Time Traveler
The first known use of fusee was in 1622

Dictionary Entries Near fusee

Cite this Entry

“Fusee.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fusee. Accessed 21 Feb. 2024.

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