H₂O Longman Dictionary of Contemporary English 5++朗文当代英语 5++LDOCE 5++朗文 5++Related topics: CompoundsH₂O /ˌeɪtʃ tuː ˈəʊ $ -ˈoʊ/ noun [uncountable] HCCthe chemical sign for water 〔水的化学分子式〕H₂O nounChinese