vane
\ veyn \ , noun;
1.a person who is readily changeable or fickle.
2.weather vane.
3.a blade, plate, sail, etc., in the wheel of a windmill, to be moved by the air.
4.any of a number of blades or plates attached radially to a rotating drum or cylinder, as in a turbine or pump, that move or are moved by a fluid, as steam, water, hot gases, or air.
5.Aerospace . a. any fixed or movable plane surface on the outside of a rocket providing directional control while the rocket is within the atmosphere. b. a similar plane surface located in the exhaust jet of a reaction engine, providing directional control while the engine is firing.
6.Ornithology . the web of a feather.
7.Navigation, Surveying . either of two fixed projections for sighting an alidade or the like.
8.Archery . feather.
Quotes:
It must be admitted that he was a vane , turning on a pivot finer than those on which statesmen have generally been made to work.
-- Anthony Trollope, "The Life of Cicero" , 1880
Spewing out “chaff,” that reanimated dead metaphor in British English for useless verbiage or humbug, the grinding nonsense of the Office serves merely as a weather vane for the clichéd winds of change.
-- Garrett Stewart, Edited by John O. Jordan, “Dickens and Language,” The Cambridge Companion to Charles Dickens , 2001
Origin:
Vane is a variant of the word fane , meaning "flag; banner." It entered English in the mid-1400s.
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