Thayer's Greek Lexicon

 1. an order, command, charge, precept, injunction
  1) that which is prescribed to one by reason of his office
2. a commandment
  1) a prescribed rule in accordance with which a thing is done
2a1. a precept relating to lineage, of the Mosaic precept
concerning the priesthood
2a2. ethically used of the commandments in the Mosaic law or
Jewish tradition