Rule of Thumb

Rule of Thumb Rule of Thumb Rule of Thumb By Maeve Maddox Reader Cynthia Turney  asks Do you know where the phrase rule of thumb came from? This is a figurative expression that means a general guideline that has a broad application, but which is not strictly accurate in every case. I hope that by now everyone knows that this expression does not come from an ancient law limiting the circumference of the stick a man could use to beat his wife. The expression originates from some forgotten literal context in which a craftsman or farmer used his thumb (about an inch) as a unit of measurement. The word rule in this expression does not mean principle or maxim as in Roberts Rules of Order. It has more to do with ruler, meaning something to measure with or a strip used for making straight lines. Body parts have long been used as units of measurement. See the DWT post Body Parts As Tools of Measurement. This Wikipedia article on rule of thumb will tell you all you can want to know about the expressions false etymology. (There used to be an article on this expression at Snopes.com, but I couldnt find it last time I looked.) Want to improve your English in five minutes a day? Get a subscription and start receiving our writing tips and exercises daily! Keep learning! Browse the Expressions category, check our popular posts, or choose a related post below:Apply to, Apply for, and Apply withWriting the CenturyHonorary vs. Honourary