ac·u·men (ăkyə-mən, ə-kymən)
Quickness, accuracy, and keenness of judgment or insight: “A brilliant acumen in agricultural matters ... had made the old man a legend in the district” (James Herriot).
[Latin acūmen, from acuere, to sharpen, from acus, needle; see ak- in the Appendix of Indo-European roots.]
Usage Note: The pronunciation (ăkyə-mən), with stress on the first syllable, has long been accepted as a standard pronunciation. It is an Anglicization of an older, traditional pronunciation (ə-kymən) that reflects the word's Latin origin. In our 2016 survey, only 34 percent of the Usage Panel found the older pronunciation acceptable (down from 60 percent in 1997), and only 14 percent preferred it, suggesting that this pronunciation is falling out of use.
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