基准标记 meaning in Chinese

fiducial marks
fiducital mark
reference mark

Road vehicles . three - dimensional reference system and fiducial marks . definitions
道路车辆.三维参考系和基准标记.定义
Phase datum mark
相位基准标记
The graduated 200 < mu > l tips have a reference mark at 10 < mu > l so you can check pipettor calibration and visually estimate sample size
200微升刻度的吸头，在10微升处有基准标记，可检查移液器刻度和估计样本容量。