The term is an English translation of several words from Hebrew, Aramaic, and Greek indicating a person or deity with power and authority. The Hebrew Adon indicates a superior or human master, with Adonai used almost exclusively for divine lordship. The BCP notes that Adonai is used in the Psalms with reference to God, and translated "Lord" (p. 583). The personal name YHWH, the "Four-letter Name" (Tetragrammaton), was the Hebrew special name for God. It was probably vocalized "Yahweh," but by around the third century B.C. it was considered too sacred to be pronounced. Adonai was most frequently substituted for it. This reverence and reticence concerning the name of God was also seen in the classical English of the Prayer Book Psalter and the OT of the King James Version, which regularly rendered the name of God as "Lord." This usage continues in the Psalter of the 1979 BCP. When Lord is used to translate YHWH, it is represented in capital and small capital letters (see Ps 150, v. 6, BCP, p. 808); but Lord is represented in capital and lower case letters when it translates Adonai (see Ps 37, v. 14, BCP, p. 634). Greek translations from the second century B.C. used kyrios for the Hebrew YHWH, and this Greek usage continued in the NT. During his earthly ministry, Jesus may have been called "lord" as a title of respect. However, after the resurrection, the title was applied absolutely by the Christian community to Jesus Christ as the Lord, so that kyrios became a confessional title for Jesus Christ in the NT (see Acts 2:36; Rom 10:9-13; 1 Cor 12:3; Phil 2:11). The full divinity of Jesus was subsequently affirmed by the Councils of Nicaea (325) and Chalcedon (451). The word "Lord" is frequently used throughout the liturgies of the Episcopal Church. For example, at the eucharist the celebrant begins the salutation by saying, "The Lord be with you." After the reading of each lesson, the reader may say, "The Word of the Lord"; and the gospeler says "The Gospel of the Lord" after the gospel (see BCP, pp. 357-358). However, the appropriateness of the term "Lord" for contemporary liturgical use has been questioned because it has been seen as a term of masculine domination. See Jehovah; see Liturgical Texts for Evaluation.
Glossary definitions provided courtesy of Church Publishing Incorporated, New York, NY,(All Rights reserved) from "An Episcopal Dictionary of the Church, A User Friendly Reference for Episcopalians," Don S. Armentrout and Robert Boak Slocum, editors.