Is the thumb a finger?

Forgive me if this has been asked before, but the search engine yielded a plethora of results.

Anyhow, my friends and I were playing Trivial Pursuit and the question “Is the thumb a finger?” came up. I had always been taught in school that the thumb is NOT a finger, but that it is a DIGIT (along with the other four digits on your hand.) The Trivial Pursuit (original Genus Edition) disagreed with my scholastic upbringing and stated the thumb is a finger.

So which is it? If the thumb is a finger, than why was I (and I presume many others) taught that it’s a digit and not a finger?

According to Merriam-Webster,

See the website http://www.m-w.com for a complete definition.
Thus, the thumb is by definition a finger, but many people don’t think of it as a finger, and use the word finger to mean non-thumb fingers.

So it all comes down to how you define “finger.” You can define it to exclude “thumb,” or to include “thumb.” No doubt the former definition was current in days of yore, while contemporary usage favors the latter.

Pianists have to be aware of this when sight-reading music printed in the 19th century. Because in the old days, the thumb was not counted as a finger, the fingerings on piano music indicated the thumb with an X. The index finger then was indicated with a 1, and so on to the little finger being 4. Modern fingering uses 1 for the thumb, 2 for the index finger, and so on to 5 for the pinky. Don’t get confused!

pleth·o·ra (plthr-)
n.

1.A superabundance; an excess.

I think that’s what he meant, gigi. As in “too many matches to wade through”.

As for the OP, I was brought up to understand that ‘finger’ was not technically meant to include the thumbs; however, a common euphemism for ‘a healthy baby’ has always been ‘10 fingers and 10 toes’. At least I don’t ever recall hearing or reading “8 fingers, 2 thumbs, and 10 toes”.

Remember what you answered when first asked how many fingers and toes you had? I guess you can safely stick with that answer.

I have a friend who lost his thumb cutting down a tree. The doctors cut off his middle finger and refashioned it as a thumb. Here, the thumb is truly a finger (and, when irate, he can give people the thumb.)
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