Stephen D. Ricks et al. discusses "Alpha and Omega" in the Book of Mormon.
Dictionary of Proper Names and Foreign Words in the Book of Mormon, ed. Stephen D. Ricks, Paul Y. Hoskisson, Robert F. Smith, and John Gee (Orem, Utah: The Interpreter Foundation, 2022), 19, 262
Alpha
Biblical DN Descriptive name for Christ (3 Nephi 9:18)
Brief etymology: The word ALPHA forms part of the phrase “Alpha and Omega, the beginning and the end,” a merism (see technical terms) itself connected to the Hebrew phrase “first and last,” mentioned twice in Isaiah.
Extended Discussion: ALPHA appears only once in the Book of Mormon as part of the phrase “Alpha and Omega,” with reference to the risen Lord in 3 Nephi 9:18. Alpha and Omega are, respectively, the first and last letters of the Greek alphabet and probably are a merism meaning not just the first and the last letters, but the whole alphabet.
The rendering of this phrase from the plates into English is probably dependent upon the King James Version rendering of Revelation 1:8, where the phrase is “I am the Alpha and Omega (koine Greek: το ‘Αλφα και το ‘Ω (transliterated as to Alpha kai to Ō in Roman characters, meaning, literally, “the Alpha and the O[mega]”), “the beginning and the end,” with reference to Christ. It occurs twice more in the book of Revelation (21:6 and 22:13). The phrase “the beginning and the end” (also found in Ecclesiastes 3;11, but not as a reference to deity) may also be connected with the merism “first and last” in Isaiah 44:6 and 48;12. According ot the Jewish folklorist Dov Noy, “the expression ‘from alef to tav’ (TB Shab. 55a and Av. Zar. 4a) corresponding to that of ‘Alpha and Omega’ (Revelation 1:8 and 22;13) denotes complete integration,” or, perhaps better said, a merism.
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Omega
Biblical DN Descriptive name for Christ (3 Nephi 9:18)
Etymology: OMEGA appears in the phrase “Alpha and OMEGA” with reference to the risen Lord in 3 Nephi 9:18. It appears to be based on the same phrase that occurs in the King James Version rendering of Revelation 1:8 where the phrase is “I am the Alpha and Omega [Koine Greek: “to Alpha kai to Ō”], the beginning and the ending,” with reference to Christ. It occurs twice more in Revelation (21:6 and 22:13). The phrase “the beginning and the end” (also found in Ecclesiastes 3;11, but not as a reference to deity) may also be connected with the merism (see glossary of technical terms) “first and last” in Isaiah 44:6 and 48;12. According to the Jewish folklorist Dov Noy, “the expression ‘from alef to tav’ (Shab. 55a and Av. Zar. 4a) corresponding to that of ‘Alpha and Omega’ (Revelation 1:8 and 22;13) denotes complete integration.”