(1) A clergyman in charge of a church or parish. (2) The head of a university or school.
Example:
We asked the rector of our church to perform the marriage ceremony.
The fiery American preacher Jonathan Edwards began as a rector of a church in Massachusetts. He was so convinced of his own ideas about rectitude and so harsh in condemning those who opposed him that he was eventually dismissed and turned out of the parish rectory where he lived. He spent his remaining years attempting to rectify the beliefs of Native Americans.