火碱 huǒjiǎn caustic soda Origin Definitions Defs Strokes Stroke Words Sentences Sents 火 huǒ noun fire fire; light and heat produced by burning; flames碱 鹼 jiǎn base; alkali (chemistry) a substance that can react with an acid to form a salt, such as a compound that releases hydroxide ions in water, accepts protons, or donates electron pairs