Search gender: all male female トサ Japanese Boy Names Variations. 1 names found. gender: all male female Name: tosa Katakana: トサ 0 Kanji: 土佐 Meaning: 土Soil 佐Auxiliary. To help. To support and help by your side. To encourage. You can save your favorite names with NAZUKE PON > About Japanese Names > Search Japanese Names By Kanji > トサ Japanese Boy Names Variations.