It became the top lookup on Merriam-Webster.com on August 23, 2010.
Frugal has become a word of the moment from online commentary about surviving the Great Recession ("think about frugal living becoming your 'new normal'"), to discussions of Jerry Brown's "frugal" campaign for governor in California, to the New York Times article "How to Be Frugal and Still Be Asked on Dates."
Frugal means "characterized by or reflecting economy in the use of resources," which helps explain its appeal: it can suggest not only belt-tightening on a personal level, but also conservation in a broader sense.
As one blogger put it, "To be frugal is sexy; to be cheap is tacky."
Frugal comes from the Latin word that also gave us fruit, as in "the fruit of your labor."