(archaic, possibly obsolete) fortress, redoubt / (archaic, possibly obsolete) important point, key

The hiragana syllable とぃ (twi). Its equivalent in katakana is トィ (twi).

(shogi, chess) A studied and standardized sequence of moves; joseki.

Synonym of 亜酸化窒素 (asanka chisso, “nitrous oxide”); dinitrogen monoxide