Old-fashioned term for Chinese characters, used in contrast with 大和文字 (yamato-moji, 'Japanese characters', i.e., kana). Rare in modern Japanese; 漢字 is the usual word.
See also: 大和文字
Long ago, Chinese characters were called 唐文字.
From 唐 (kara, 'Tang dynasty; China') + 文字 (moji, 'characters'). The exact historical derivation is uncertain, but the term reflects an older period when 'Tang' was a general name for China.