‖n. [ Heb. adōnāi, lit., my lord. ] A Hebrew name for God, usually translated in the Old Testament by the word “Lord”. [ 1913 Webster ]

☞ The later Jews used its vowel points to fill out the tetragrammaton Yhvh, or Ihvh, “the incommunicable name, ” and in reading substituted “Adonai”. [ Webster 1913 Suppl. ]