"Run the gamut"

Heard this today. Amazing how we use a-word-in-a-phrase with no idea whatsover what that word means.

What's a gamut?

That is a really odd word and an odd phrase. So it was "the gamut" as in "the entire scale"?

And why are we always running the gamut - why never walking or skipping?

Interesting word. I looked it up in the online OED, and their 4th definition seemed the most relevant.

~ Their first comes from 1530 and is "The first or lowest note in the mediæval scale of music, answering to the modern G on the lowest line of the bass stave."

~ The next comes from 1529, and is The 'Great Scale.'

~ Hence in later use (from 1709): "The whole series of notes that are recognized by musicians. Sometimes also used for: The major diatonic scale, or the ‘scale’ recognized by any particular people, or at any period."

~ Next up is from 1626, and most relevant for our current usage: "The whole scale, range, or compass of a thing." For this use, they have 2 relevant quotes, one from Burton and one from Harper's Mag.: (1) 1864 BURTON Scot Abr. III. i. 122 He ran over the gamut of Latin metre. (2) 1883 Harper's Mag. 822/2 The..stocks were running..up and down the gamut from $1 to $700 a share.

~ Lastly they combine it with "string" for "gamut-string," from 1674.