Tonden refers to a system or the place/region where soldiers who were made to plow new fields were recruited at war time but farmed the land to sustain themselves at peace time.
屯田（とんでん）は、一般に、兵士に新しく耕地を開墾させ、平時は農業を行って自らを養い、戦時には軍隊に従事させる制度、またその場所や地域を言う。