Naming the Isosceles Triangle
Date: 09/23/98 at 23:44:24 From: Caron Harris Subject: Isosceles triangle name One of my 7th grade reading students wanted to know how the isosceles triangle received its name.
Date: 09/24/98 at 04:05:26 From: Doctor Mike Subject: Re: Isosceles triangle name Hi, The mystery can be resolved by looking in almost any good dictionary. The word is of Greek origin, coming from isos, meaning equal, and skelos, meaning leg. Looking up the etymology of a word or two in a reading assignment would be a good habit to encourage for your 7th graders. Are you actually using material with some mathematical content for general reading instruction? Fantastic! - Doctor Mike, The Math Forum http://mathforum.org/dr.math/
Date: 09/24/98 at 07:28:29 From: Darla or Caron Subject: Re: Isosceles triangle name Thank you. We thought maybe there was more to it than just that. You're right; I also found that in a dictionary. In our reading classes, we teach all subjects and hit on all disciplines. Thanks again. Caron
Date: 10/07/98 at 13:06:31 From: Doctor Mike Subject: Re: Isosceles triangle name Hello again, Caron, You're very welcome. You may be right, too. Many words of Greek or Latin origin are thoroughly modern inventions, like "isotope," which relate to scientific concepts not known to the ancients. However it appears that isosceles is somewhat different. My dictionary says that isosceles is an actual Latin word, coming from the actual Greek word isoskeles. This makes sense really. The Greeks pretty much owned geometry back then, so they must have had a word for this. They would have used the same roots "isos" and "skelos" to form the word. But since the concept was known to them, we didn't have to wait for modern mathematicians to invent the word. From my very limited knowledge of Greek, I'm pretty sure Euclid and the others did not pronounce it the same, probably something sounding like EE - SO - SKAY - LEASE. To me it is sort of neat to know I am saying the same word that they were using for this idea 2500 years ago! By the way, the word "scalene" for a triangle with 3 different leg lengths comes from another Greek word "skalenos" meaning uneven. I was mentioning this question to one of my kids, who clued me in to the interesting etymology for helicopter. The two Greek roots are the same as for HELIx and PTERodactyl. Next time you are reading about flying things from Jurassic to Modern times this could come in handy. Thanks for writing. - Doctor Mike, The Math Forum http://mathforum.org/dr.math/
Search the Dr. Math Library:
Ask Dr. MathTM
© 1994- The Math Forum at NCTM. All rights reserved.