ˌmirēōˈfiləm noun
Usage: capitalized
Etymology: New Latin, from Latin myriophyllon water milfoil, from Greek, from myrio- myri- + phyllon leaf — more at blade
: a widely distributed genus of submerged aquatic plants (family Haloragaceae) having much-divided whorled or alternate leaves and emersed wind-pollinated flowers — see water milfoil