蒸散 Traditional form: 蒸散 Pinyin (reading): zhēngsàn Definitions: (plant) evapotranspiration Characters: 蒸 - steam, vapor; to evaporate 散 - to scatter, to disperse, to break up Traditional characters: 蒸 - steam, vapor; to evaporate 散 - to scatter, to disperse, to break up