丝氨酸 Traditional form: 絲氨酸 Pinyin (reading): sī'ānsuān Definitions: serine (Ser), an amino acid Characters: 丝 - silk, fine thread; wire; strings 氨 - ammonia 酸 - tart, sour; spoiled; acid Traditional characters: 絲 - silk, fine thread; wire; strings 氨 - ammonia 酸 - tart, sour; spoiled; acid