Mnemonic Metric Prefixes

By The Metric Maven

Integer Solar Orbit Day

Engraving of Kilroy on the WWII Memorial in Washington DC

Years ago, my friend Ty took an interest in how to remember information. He pointed out that often you will think of something you want to do or retrieve, leave the room where you made the decision, and by the time you arrive in the next room, have forgotten. Often you return to the the original room, and then suddenly can recall what you meant to retrieve or view. Ty asserted it was because you had associated the decision with the original room, and when you returned, the two things were attached in your mind and you immediately recalled why you left in the first place. Years ago, when I was a young boy, people would tie a string around their finger to remind them to remember an important piece of information.

When I was taking trigonometry in high school, the teacher indicated we should remember words and phrases to recall the definitions of the sine, cosine, and tangent of a right triangle. He offered:

The adjacent side of the triangle was closest to the angle, the opposite side was well, opposite of the angle, and the hypotenuse was the long side that was not the others. Silly Cold Tigers? and Oscar Had A Happy Old Aunt?—how ridiculous!—but decades later, I still remember this method of recalling the definitions of the basic trigonometric functions of a right triangle. He encouraged his students to make up their own, and indeed they came up with more memorable phrases that were the sort that teenage boys were more likely to remember.

A number of “metric advocates” have ridiculed my assertion that grade school children, middle school students, and high school pupils, should be instructed in the use of all the metric prefixes. In my view, all the prefixes means the eight magnifying and eight reducing prefixes separated by 1000. One of the most effective instructive methods for recalling information is the use of a mnemonic device. Here I propose a pair of these, one for the magnifying prefixes, and one for the reducing prefixes. The first mnemonic is presented in the table below for the magnifying prefixes:

The mnemonic phrase for the magnifying prefixes is: “Kilroy Might Get To Paris Escorting Zombies Yonder.” The first letter of each word corresponds to the prefix symbol. The first prefix is Kilo is suggested by the name Kilroy, but the rest of the prefixes all end with an “a.” This can be thought of as the prefixes “above” unity.

The second table for the reducing prefixes is:

The mnemonic phrase for the reducing prefixes is “Millie might not protest fetching another zesty yeti.” Again the first letter of each word corresponds to the prefix symbols except for micro. The student would have to spell out micro and then recall the μ symbol is used, rather than another m. The first word is again a name, Millie, which in this case contains the spelled out prefix. Again means we need to forget it, but realize the reducing prefixes all end with “o” and are “below” unity.

In both cases the phrase begins with a name, and involves that person compelling mythical creatures.

If students were taught these mnemonics from perhaps grade 6 or 7 onward, with metric prefix examples, like those found in The Dimensions of the Cosmos, by the time they graduated from high school, they could have the tools needed to recall the metric prefixes without a textbook, and be reminded to use them in their work.

I would be interested in any comments or suggestions readers might have about these proposed mnemonic devices that might improve them. The best way to promote their use would be for the US to become a mandatory metric nation, but as this country celebrates its reactionary nature with religious fervor, I’ll have to settle for whatever good these mnemonics might do without a change.

If you liked this essay and wish to support the work of The Metric Maven, please visit his Patreon Page and contribute. Also purchase his books about the metric system:

The first book is titled: Our Crumbling Invisible Infrastructure. It is a succinct set of essays  that explain why the absence of the metric system in the US is detrimental to our personal heath and our economy. These essays are separately available for free on my website,  but the book has them all in one place in print. The book may be purchased from Amazon here.

The second book is titled The Dimensions of the Cosmos. It takes the metric prefixes from yotta to Yocto and uses each metric prefix to describe a metric world. The book has a considerable number of color images to compliment the prose. It has been receiving good reviews. I think would be a great reference for US science teachers. It has a considerable number of scientific factoids and anecdotes that I believe would be of considerable educational use. It is available from Amazon here.

The third book is called Death By A Thousand Cuts, A Secret History of the Metric System in The United States. This monograph explains how we have been unable to legally deal with weights and measures in the United States from George Washington, to our current day. This book is also available on Amazon here.

2 thoughts on “Mnemonic Metric Prefixes

  1. Would it help to have a tune to sing these mnemonics to? I can almost make them fit “Supercalifragilisticexpialidocious” or the chorus to Beethoven’s 9th Symphony.

    Also, wishing you congratulations on another solar circumnambulation.

  2. “A number of “metric advocates” have ridiculed my assertion that grade school children, middle school students, and high school pupils, should be instructed in the use of all the metric prefixes.”

    I wouldn’t call them metric advocates if they don’t support the proper teaching of SI, which is to know all of the prefixes and the correct unit symbols. I don’t think young children learning the prefixes need a mnemonic as at their age they can easily learn and retain new information. They need to be taught to use all of the prefixes when and where applicable. If taught correctly and encouraged, they will keep this practice for life.

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