I discovered today that the French word for thumb, pouce, also means inch, which makes sense as the length of the inch is apparently based on the width of a man’s thumb.
Related expressions include:
– se tourner les pouces, se rouler les pouces = to twiddle one’s thumbs
– manger sur le pouce = to grab a quick bite to eat (“to eat on the thumb”)
– déjeuner/dîner sur le pouce = to have a quick lunch/dinner (“to lunch/dine on the thumb”)
– donner un coup de pouce à quelqu’un = to help someone out (“to give a blow of the thumb to sb”)
– mettre les pouces = to throw in the towel; to give in; to give up (“to put the thumbs”)
The word inch comes from the Latin word uncia (a twelfth; ouce; inch), as does the word ounce, which is a twelfth of a troy pound [source]
The word for inch is the same as the word for thumb in Italian (pollice), Dutch and Afrikaans (duim), and Czech and Slovak (palec). How about in other languages?