E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Gear (g hard)
properlymeans dress. In machinery, the bands and wheels that communicate motion to the working part are called the gearing. (Saxon, gearwa, clothing.)
1
In good gear. To be in good working order.
2
Out of gear. Not in working condition, when the gearing does not act properly; out of health.