Echad does not mean "compound one"

It is rather common to hear from some Trinitarian apologists that the Hebrew ordinal אֶחָד in Deut 6:4 (NASB: Hear, O Israel! the Lord is our God, the Lord is one [אֶחָד]) is a compound or "plural" one, so this "oneness" allows for a plurality of persons within the one God (e.g., Robert Morey, The Trinity: Evidences and Issues [1996]). This is perhaps one of the most inane attempts to salvage belief in the Trinity, and one that is not supported by the leading, scholarly lexicons of biblical Hebrew. This nonsense claim has been soundly refuted by Anthony Buzzard, a well-known proponent of Unitarianism. Here is an excerpt from his 2007 book Jesus was not a Trinitarian here. While I disagree with his Socinian Christology, and believe he is grossly ignorant on the topic of “Mormonism,” what he writes is very sound vis-à-vis the meaning of אֶחָד and its abuse by the likes of Michael Brown, Robert Morey, et al.

Here is the entry under אֶחָד from Koehler-Baumgartner, Hebrew and Aramaic Lexicon of the Old Testament (HALOT), perhaps the Hebrew lexicon on the market at the moment:

312  אֶחָד

) אֶחָד960 x(, Sam.^M18 ÁaÒd: < *ÀahÌhÌaÒd < *ÀahÌad )Arb., BL 219g, Beer-M. §59:1(, ï יָחִיד; MHb., Ug. ahÌd, f. ahÌt, Ph. אחד, f. אחת, Arm. ) חַדï BArm. MdD 116a(, Eth. ÀahÌaduÒ, Akk. )w(eÒdu: abs. אֶחָד, and אַחַד Gn 48₂₂ + 5 x )BL 622b(, cs. אַחַד, חַד Ezk 33₃₀ )Aramaism or text error ? Nöldeke Syr. Gr. §242(, pl. אֲחָדִים; fem. ) אַחַת< *ÀahÌadt( abs. and cs., אֶחָֽת Gn 11₁, 2S 23₈ Q:

—1. numeral one a( מָקוֹם אֶ׳ one )single( place Gn 1₉, בְּשָׁנָה אֶחָת Ex 23₂₉, בְּרָכָה אַ׳ Gn 27₃₈, נֶפֶשׁ אַ׳ one soul = one single person Lv 4₂₇, אֶ׳ :: שְׁנֵי two :: one Lv 14₁₀; מִשְׁפָּט אֶ׳ the same law Nu 15₁₆, דָּתוֹ אַ׳ the same law is in force Est 4₁₁ מִדָּה אַ׳ the same measure Ex 26₂; אֶחָד י׳ Dt 6₄ Y is one )Sept., Pesh., Stade Theologie 1:84(; alt.: the one Y, Y alone, Y only; אֶ׳ one and only Zech 14₉ , the same )?( Jb 31₁₅ alt. one; ï TWNT 3:1079f; vRad Theologie 2:226; Eichrodt Theologie 1:145, Labuschagne 137f; b( part. )VG 2:273aאַחַד הָעָם ( one of the people 1S 26₁₅, הַנְּבָלִים אַ׳ 2S 13₁₃, אַחַת הַנְּבָלוֹת Jb 2₁₀ אֲחִיכֶם אֶ׳ one of you brothers Gn 42₁₉, מִכֶּם אִישׁ אֶ׳ a single one of you Jos 23₁₀, מִמֶּנּוּ ) אַ׳GK §130a( one of us Gn 3₂₂; c( negative form: אֶ׳ … לֹא Ex 8₂₇ and לֹא אַחַד) עַד־אַ׳ abs., BL 622b( 2S 17₂₂ not one, גַּם אֶ׳ ˆyae not even one Ps 14₃ עַד אֶ׳ … לֹא not even one Ex 14₂₈; d( קוֹל אֶ׳ with one voice Ex 24₃, לֵב אֶ׳ 1C 12₃₉ cj. Ps 83₆ )rd. וְ (אֶחָד unanimous, שְׁכֶם אֶ׳ shoulder to shoulder Zeph 3₉; לְיוֹם אֶ׳ for a single day, daily 1K 5₂, cj. Neh 5₁₅ for אַחַר; אֶ׳ יוֹם never-ending day Zech 14₇; ) אַחַתsc. (פַּעַם אַ׳ once: בַּשָּׁנָה אַ׳ Ex 30₁₀ Lv 16₃₄; אַ׳ :: שְׁתַּיִם once … twice 2K 6₁₀ Ps 62₁₂ )?, ï שְׁתַּיִם( Jb 40₅; בְּאַחַת Jr 10₈ and כְּאֶחָד Qoh 11₆ in one and the same time; )ï BArm. כַּחֲדָה, Aramaism Arm.lw. Wagner 124; Akk. kiÒma isëteÒn(, אַחַת Ps 89₃₆ and בְּאַחַת Jb 33₁₄ once and for all; הוּא אֶ׳ only one Gn 41₂₅, אֶחָד … וַיְהִי became one, a unit Ex 36₁₃; וְהָיָה הַמִּשְׁכָּן אֶחָד a single whole Ex 26₆; in statistical records repeated after each name Jos 12_9-24 cj. 1K 4_8-18 )Sept.(, Montgomery-G. 124; e( pl. אֲחָדִים: יָמִים אֲ׳ a few days Gn 27₄₄ 29₂₀ Da 11₂₀ אֲ׳ µyrIb;D“ the same )kind of( words Gn 11₁ Ezk 29₁₇ ):: Gordon UTGl. 126: like Ug. ahÌdm du. “a pair”( וְהָיוּ לַאֲ׳ to become one Ezk 37₁₇;

—2. אֶ׳ one another )VG 2:328f(: וּמִזֶּה אֶ׳ מִזֶּה אֶ׳ one here and one there Ex 17₁₂, בְּאֶ׳ אֶ׳ one to another Jb 41₈, cj. אֶחָד אֶת־אֶחָד vs. Ezk 33₃₀ one to another, with gloss אִישׁ אֶת־אָחִיו; וְאֶ׳ … וְאֶ׳ … אֶ׳ one … another … a third 1S 10₃ 13_17f, וְהָאֶ׳ … òa,h; one … and the other 1K 12₂₉, הֵנָּה אַחַת הֵנָּה וְאַ׳ once here and once there = to and fro 2K 4₃₅ לְאַ׳ אַחַת one after the other Qoh 7₂₇, וְהַדּוּד אֶ׳ … dj;a, הַדּוּד Jr 24₂ the one basket … and the other )Brockelmann Heb. Syn. §60b, 1S 13₁₇ (הָרֹאשׁ אֶ׳;

—3. אֶ׳ indefinite article )GK §125b( אִישׁ אֶ׳ 1S 1₁, נָבִיא אֶ׳ 1K 13₁₁, אַיִל אֶ׳ Da 8₃, יוֹם אֶ׳ one day 1S 27₁, יִשְׂ׳ אַחַד שִׁבְטֵי anyone of the tribes 2S 15₂, ) מֵאַחַת מֵהֵנָּהGK §119w¹( any one of them Lv 4₂; put in front קָדוֹשׁ אֶ׳ a holy one Da 8₁₃, אַחַת מְעַט הִיא for a little while Hg 2₆ מְעַט הִיא) > Sept.(;

—4. ordinal, first: אַחַת :: הַשֵּׁנִית 1S 1₂, יוֹם אֶ׳ the first day Gn 1₅ ):: יוֹם שֵׁנִי 1₈ etc.(; in dates לַחֹדֶשׁ בְּיוֹם אֶ׳ on the first day of the month Ezr 10₁₆ > לַחֹדֶשׁ בְּאֶ׳ Gn 8₅, בִּשְׁנַת אַחַת לְ in the first year of Da 9₁, וְשֵׁשׁ מֵאוֹת שָׁנָה בְּאַחַת in the 601st year Gn 8₁₃;

—5. distributive: לַשֶּׁבֶט אֶ׳ one in each tribe Dt 1₂₃, לְאִישׁ אֶ׳ from each man 2K 15₂₀, לְאַחַד אֶחָד one after the other Is 27₁₂, לְאֶחָֽת each single one Ezk 1₆, הָאַחַת each 1C 27₁;

—Gn 32₉ rd. הָָאֶחָד; 2S 2_25b dl.; 7₂₃ and Ezk 17₇ ):: Zimmerli 374( rd. אַחֵר, Ezk 11₁₉ rd. אַחֵר or חָָדָשׁ; Jb 23₁₃ rd. בָּחַר for ) בְּאֶחָד:: Dahood Fschr. Gruenthauer 67(, Pr 28₁₈ rd. בְּשָֽׁחַת; Qoh 12₁₁ cj. ) אָחוֹרGalling BASOR 119:18(; Da 8₉ rd. אַחֶרֶת.