late 13c., "to mingle," from O.N.Fr. medler (O.Fr. mesler) "to mix, mingle, to meddle," from V.L. *misculare, from L. miscere "to mix" (see mix). Meaning "to concern oneself" (usually disparaging) is attested from early 15c. From mid-14c. to 1700, it also was a euphemism for
"have sexual intercourse." Related: Meddled; meddler; meddlesome; meddling.