phylloxeraPronunciation: /ˌfɪlɒkˈsɪərə, fɪˈlɒksərə/Definition of phylloxera noun a plant louse that is a pest of vines. Phylloxera vitifoliae, family Phylloxeridae, suborder Homoptera Origin: mid 19th century: modern Latin, from Greek phullon 'leaf' + xēros 'dry'phylloxera in other Oxford dictionaries Definition of phylloxera in the US English dictionary