Godhi is a Northern term that translates roughly as "priest" and is used in Midhgardhur for a holy man dedicated to the gods (usually one of the Aesir). The plural is godhar.
Gydhja is the feminine equivalent term - roughly "priestess" - for which the plural is gydhjur.
The power to work miracles and wonders through prayers is attributed to godhar and gydhjur in Midhgardhur, derived from the priest's or priestess' special connection to their gods. A godhi or gydhja often takes this title as part of their surname, e.g. Bosi, a godhi of Thorr, might be known as Bosi Thorsgodhi = Bosi, Thorr's godhi.