GangmChinese From Chinese 刚 (gāng) meaning "hard, rigid, strong", as well as other characters with a similar pronunciation.
TsuyoshimJapanese From Japanese 剛 (tsuyoshi) meaning "hard, rigid, strong". It can also come from an alternate reading of 剛 (tsuyo) combined with 史 (shi) meaning "history" or 志 (shi) meaning "will, purpose". Other kanji and kanji combinations can also form this name.