Origin: Latin suffix -ive
Overdrive has 6 different meanings across 2 categories:
the state of high or excessive activity or productivity or concentration
"Troops are ready to go into overdrive as soon as the signal is given"
"Melissa's brain was in overdrive"
a high gear used at high speeds to maintain the driving speed with less output power
"The driver shifted into overdrive on the highway so the engine wouldn't labor while maintaining sixty miles per hour."
A gear, on an automobile, higher than the normal top gear.
"The driver shifted into overdrive to let his car coast down the long highway without touching the brakes."
drive or work too hard
"The teacher is overworking his students"
"Overdriving people often suffer stress"
To drive too hard, or far, or beyond strength.
"After working two double shifts in a row, I had to pull over because my body was finally screaming that I had gone into overdrive."