History of the Word

Date: 08/21/2006 at 18:10:05
From: David
Subject: Why is ruler called a ruler

I was just wondering, why is a ruler called a ruler?

Date: 08/21/2006 at 20:31:23
From: Doctor Rick
Subject: Re: Why is ruler called a ruler

Hi, David.

Do you  sometimes look at a word you see every day, and suddenly it 
seems strange?  I do that.  I, too, wonder how a word can mean two 
things that seem very different.  The history of words (called 
etymology) has lots of strange stories that sort of make sense when 
you think about them.

A good place to start answering questions about words is a dictionary.  
Looking in my dictionary (Random House Webster's College Dictionary), 
the etymology listing under "rule" says this:

[1175-1225; (n.) ME riule, reule < OF riule < L regula straight stick, 
pattern, der. of regere to fix the line of, direct (see -ULE).

In other words: The word was first used around 1200.  Before that (in 
"Middle English", it was spelled with an "i" or an "e".  Why?  Because 
it was spelled that way in Old French.  The French took the Latin word 
"regula", dropped the g and changed the a to a silent e.  (The French 
did that sort of thing a lot, dropping letters and not pronouncing a 
lot of the letters they kept!)

The Latin word "regula" meant a straight stick.  That's a ruler: a 
device for making straight lines.  Whether the Romans put marks on 
their rulers to measure lengths, I don't know, but apparently the most 
important thing about it was that it was straight.

Why do I say that?  Because it comes from the word regere, which meant 
"to guide or direct, to make straight."  When you use a ruler to make 
a line, it keeps the line from going astray in either direction; it 
guides your pencil the way you want it to go.

Now that we know that the word from which we get "rule" or "ruler" had 
"a straight stick" as its primary meaning, our question gets turned 
around: How did "rule", meaning "a stright stick", come to mean "tell 
others what to do", or "a law that we have to follow"?  But maybe you 
can already see the answer.  A ruler sets the standard; it's a pattern 
to be followed.  If you put a ruler next to a line, you can tell right 
away if the line is crooked.  A rule or regulation (notice where 
*this* word comes from?) sets a standard, so everyone knows if you 
"break the rule".  Someone who sets the rules for others to follow is 
called a ruler.

There are lots of other words related to rule, ruler and regulation. 
Something that is "regular" follows the rules; something irregular 
breaks the rules.  The Romans put the prefix de- in front of regere 
and it became derigere: to straighten or direct--we get the word 
direct (and the word dirigible, something that can be steered) from 
derigere.  And notice the "rect" part of direct: all sorts of words, 
such as rectangle, and even right (angle), come from Latin rectus, 
which means "made straight" from regere, to make straight.  There's 
more on that here:

  Left Angles
    http://mathforum.org/library/drmath/view/58420.html 

If you found that interesting, I hope you can take a Latin class in a 
few years.  You'll learn a lot about words that way.  If you lost 
interest after the first paragraph, ... anyway, I'm done now.

- Doctor Rick, The Math Forum
  http://mathforum.org/dr.math/