phylactery
The origin and history of phylactery.
Etymology
Phylactery reached English through Late Middle English forms such as philacterie, from Late Latin phylacterium, itself from Koine Greek phŭlăktḗrĭon, meaning amulet or tefilla. That Greek word was used in the New Testament to translate the Hebrew word for tefillin, and traces back further to an Ancient Greek word for a guarded post or safeguard, related to a verb meaning to guard or protect.
