Military Ranks

I wanted to check the word origins of certain military ranks (too many stories about The Watch, Vimes and Nobby can do that to you) .

So here goes.

From the Online Etymology Dictionary:

Corporal:
From 16th Century. Quote: "So called because he was in charge of a body of troops".
Check the other meaning on that link. Good to know the humble origins of corporal punishment.
So they weren't kidding when they said schools are becoming more and more like a military camp.

Sergeant:
Dates back to the 13th Century. Looks like the meaning evolved a bit through time.
But the general meaning is one who serves or carries out the law.
Quote: "officer whose duty is to enforce judgments of a tribunal or legislative body" is from c.1300

Lieutenant:
My aren't you a fancy little sub at the Russian front. Well, this word basically means "placeholder". Dates as far back as 1375. Quote: "substitute" for higher authority.

Colonel: The word might have its origins in the word meaning a pillar. It evolved to be "commander of a column of soldiers at the head of a regiment,".