What Can You Find in an Etymological and Historical Dictionary of Math, be surprised.

Early in my teaching career I developed an interest in the origin of mathematical terms and symbols, and the origins of the sometimes unusual terms, like Frustum, or isosceles, or leptokurtic, so I began to study, and share things with my classes as I found them. They seemed genuinely interested when I would introduce such matters in class, but when I heard one of my students explaining one of the terms to a friend in the hall, I knew I should compile a record for myself of what I found, and not rely on memory. Then I could refresh my memory much quicker, and plan the most appropriate spot to introduce the information to support my instruction. I eventually built a resource on the Internet, but when I retired, the access went with it.

Recently, I have started to recreate an Etymological and Historical Dictionary of Math, and have posted the first few volumes(A-E) at this writing. As I was compiling my notes for G-H-I, I got an email from a reader who asked.. well, the title of this posting. So to answer, here is the post for two words on the current volume, that most teachers wold think they are fully conversant on. So read, and if you find something that intersests you, or sparked you imagination, or might interest your classes, Then check out the Early Volumes

And here is the promised Preview:

Geometry is derived from the Greek word for the earth, geos, from the Goddess Gaia, and the term for "to measure", metros.  Literally then, geometry means "to measure the earth" and that was it's original purpose.  Although the Greeks and Latins pronounced the name of the Earth Goddess as gay' yuh, it came into English pronounced more like Jee' uh, from which we get many geos related words like geography, and geology. 

Just as the study of the Earth, geology, recalls the ancient Greek God of the sky, the term Uranology, from the Greek God Ouranos, is the study of the sky, but the more common term today is astronomy.  But do not despair for the lost memory of the god of the sky, for he is preserved in the name of the planet discovered by Wiliam Herschel in 1781.  Although Herschel wanted to name the planet in honor of King George III, remembered as the bad guy of the American revolution by US History, Johann Bode (see Bode's Law) came up with the name that stuck, Uranus.   The sky god is also remembered through a discovery a few years later (1798) by chemist Martin Klaproth.  It was a tradition to name metals after planets, so Klaproth named his new metal after the new planet, calling it Uranium.  Later he found another metal and decided to name it after the Earth, but instead of using the Greek Goddess of the Earth, he chose to use the Roman equivalent and called the new metal tellurium. The Roman Goddess of the Earth was known by two names.  The first was Terra, from which we draw words like terrestrial, and its better known opposite, extra-terrestrial. The other name was Tellus which is almost non-existent today, except in the name of Klaproth's metallic discovery.  

Hundred is from the German root hundt. The quantity that it represents has not been consistent over the years, or from place to place.  It has ranged in value from its common present value of 100, to 112, 120, 124 and 132 at different times and places.  The remnants of these old measures still persist in the hundredweight in some countries representing 112 or 120 pounds, depending on the country. Shortly after the US adopted 100 pounds as the  hundredweight as a standard, the UK formalized 112 pounds, and outlawed the US measure. The weight is still used, I believe, in the Imperial system. In Germany the hundredweight was 120 pounds, and has since been modified to Long Hundred.  

A hundred has also been used to represent an area of land equal to 100 hides (the general size of a hide came from the German for the amount of land necessary to support a family, the land measure of Hundreds usually measured from 60 to 120 acres {there's that Long hundred again. }). The measure of area was frequently used in colonial US and parts of England in place of the "shire" or "ward".   A curious custom related to one hundred as a unit of land occurs in England when a member of the house of commons wishes to resign his seat, which is illegal.  An MP accepts stewardship of the "Chiltern Hundreds", an area of chalk hills near Oxford and Buckingham, and effects his release.   

Your comments and corrections are always appreciated.