A device for measuring the revolutions per minute (RPMs) of a revolving shaft, as with the driveshaft of an automobile.speedometer

It’s the thing on the left here, measuring the RPMs of the engine, which is to say how hard the engine is working. Which IIRC is how you can tell when to shift when driving a manual transmission.

Wikipedia: “Essentially the words tachometer and speedometer have identical meaning: a device that measures speed. It is by arbitrary convention that in the automotive world one is used for engine and the other for vehicle speed.”

Personally I’d have more use for a taco-meter. 🌮

He looked back like a nocturnal rabbit trying to outstare the headlights of a sixteen-wheeled artic whose driver is a twelve-hour caffeine freak outrunning the tachometers of hell.

Terry Pratchett, Mort

Definition from Wiktionary, Creative Commons Attribution/Share-Alike License (via Wordnik)
Image from Wikipedia

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s