English edit

Etymology edit

free +‎ hub, from a trademark.

Noun edit

freehub (plural freehubs)

 
Shimano freehub
 
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  1. A type of bicycle hub incorporating a ratcheting mechanism, with a cassette, or set of sprockets, mounted onto a splined shaft of the hub to engage the chain.
    In many high-end and midrange bicycles, freehubs have replaced freewheel systems.

See also edit