There are 18 words that start with 'gear'.
| gear | gears | geared |
| gearbox | gearing | gearcase |
| gearhead | gearings | gearless |
| gearboxes | gearcases | gearheads |
| gearshift | gearwheel | gearchange |
| gearshifts | gearwheels | gearchanges |
Note: These 18 words that start with 'gear' are found from the USA & Canada version of the tournament Scrabble word list.