Exert is defined as to put forth or into use with great energy.(verb)
An example of exert is to put lots of energy into exercising.
See exert in Webster's New World College Dictionary
Origin: L exsertare, freq. of exserere, to stretch out, put forth < ex-, out + serere, to join, fasten together: see series
See exert in American Heritage Dictionary 4
transitive verb ex·ert·ed, ex·ert·ing, ex·erts
Origin: Latin exserere, exsert-, to put forth, stretch out
Origin: : ex-, ex-
Origin: + serere, to join; see ser-2 in Indo-European roots.
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