中性染料 meaning in English

neutral dye
neutral stain

Neutral dyes - determination of dyeing shade and relative strength
中性染料染色色光和强度的测定
Unified test method for neutral dyestuff
中性染料统一检验方法
Not stained strongly or definitely by either acid or basic dyes but stained readily by neutral dyes . used especially of white blood cells
嗜中性染料的不一定非用酸性或碱性染剂染色不可的，也易于用中性染剂染色的，尤其指白细胞