![double centering double centering](https://www.tekportal.net/wp-content/uploads/2018/12/double-centering.png)
double centering noun Surveying.
- a method of extending a survey line by taking the average of two foresights, one with the telescope direct and one with it inverted, made each time by transiting the telescope after a backsight.
double centering noun Surveying.