Definition from Nolo’s Plain-English Law Dictionary

1) To conduct the duties of a job or position. 2) To manage the affairs of the estate of a person who has died under supervision of the local probate court. 3) To give an oath to someone who is about to testify in court or assume governmental office, as in "administer the oath." (See also: executor, probate)

Definition provided by Nolo’s Plain-English Law Dictionary.