苏氨酸 sū'ānsuān threonine Origin Definitions Defs Strokes Stroke Words Sentences Sents 苏 蘇 sū proper nounnoun phonetic Used in transliteration for foreign names like 苏丹 sūdān (Sudan) or 苏里南 sūlǐnán (Suriname)氨 ān noun ammonia Chemical compound of nitrogen and hydrogen that is a colorless gas with a pungent smell; commonly used in fertilizers and refrigerants.酸 suān noun acid acid, a chemical compound that releases hydrogen ions in water