fullback
noun [ C ] uk/ˈfʊl.bæk/ us/ˈfʊl.bæk/
（足球、曲棍球等中的）防守后卫;（美式橄榄球中控球方的）后卫
a defending player in games such as football and hockey who plays near the end of the field, or an attacking player in American football whose position is behind the quarterback and beside the halfbacks