√ hâyâh — to exist, iConjunctive wawVerbQalConsecutive imperfectthird person masculine singular
וַיְהִ֣י (H1961, hâyâh) — "and it came to pass," the narrative wayhî that opens a decisive turn; the same verb-form will recur in v.30 (wat·tə·hî, "and there was" a great cry), framing the whole stroke between two acts of God's bringing-to-pass.
בַּחֲצִ֣יba·ḥă·ṣîat midnightH2677 √ chêtsîy — the half or middlePreposition-bNounmasculine singular construct
בַּחֲצִ֣י (H2677, chêtsîy) — "at the half/middle of," construct; the precise hinge of the night. Poole: "At midnight; a great aggravation of the plague; for then darkness itself strikes men with horror, and makes any calamity more terrible."
הַלַּ֗יְלָהhal·lay·lāh. . .H3915 √ layil — properly, a twist (away of the light), iArticleNounmasculine singular
וַֽיהוָה֮Yah·wehthe LORDH3068 √ Yᵉhôvâh — Jehovah, Jewish national name of GodConjunctive wawNounpropermasculine singular
וַֽיהוָה֮ (H3068, Yᵉhôvâh) — "and YHWH," the national covenant Name of God. The actor is named in full at the verse's center. Barnes notes the plague is "distinctly attributed... to the personal intervention of the Lord," even as 12:23 also names "the destroyer."
הִכָּ֣הhik·kāhstruck downH5221 √ nâkâh — to strike (lightly or severely, literally or figuratively)VerbHifilPerfectthird person masculine singular
הִכָּ֣ה (H5221, nâkâh, Hifil) — "struck," the smiting-verb of the plagues. Gill sets the scene: the blow fell "when fast asleep, and thoughtless of any danger; and it being at such a time must strike with a greater horror and terror."
√ kôl — properly, the wholeNounmasculine singular construct
בְּכוֹר֮bə·ḵō·wrfirstbornH1060 √ bᵉkôwr — firstbornNounmasculine singular
בְּכוֹר֮ (H1060, bᵉkôwr) — "firstborn." Ellicott restricts the term: "All the firstborn. —The Hebrew word used applies only to males." The word will toll five times across these two verses, the dirge of the chapter.
בְּאֶ֣רֶץbə·’e·reṣmale in the landH776 √ ʼerets — the earth (at large, or partitively a land)Preposition-bNounfeminine singular construct
מִצְרַיִם֒miṣ·ra·yimof EgyptH4714 √ Mitsrayim — Mitsrajim, iNounproperfeminine singular
מִבְּכֹ֤רmib·bə·ḵōrfrom the firstbornH1060 √ bᵉkôwr — firstbornPreposition-mNounmasculine singular construct
פַּרְעֹה֙par·‘ōhof PharaohH6547 √ Parʻôh — Paroh, a general title of Egyptian kingsNounpropermasculine singular
פַּרְעֹה֙ (H6547, Par‘ōh) — "Pharaoh," a general title of Egyptian kings. His firstborn is the heir who "sat on his throne"; the loss, Ellicott notes, "would be felt as a national calamity."
הַיֹּשֵׁ֣בhay·yō·šêḇwho satH3427 √ yâshab — properly, to sit down (specifically as judgeArticleVerbQalParticiplemasculine singular
הַיֹּשֵׁ֣ב (H3427, yâshab) — "the one sitting," Qal participle, with the article; the verb "to sit (specifically as judge, in ambush, in quiet)" used here of enthronement — Pharaoh's heir on the seat of rule, the highest pole of the merism.
√ ʻal — above, over, upon, or against (yet always in this last relation with a downward aspect) in a great variety of applicationsPreposition
כִּסְא֔וֹkis·’ōwhis throneH3678 √ kiççêʼ — properly, covered, iNounmasculine singular constructthird person masculine singular
√ ʻad — as far (or long, or much) as, whether of space (even unto) or time (during, while, until) or degree (equally with)Preposition
בְּכ֣וֹרbə·ḵō·wrthe firstbornH1060 √ bᵉkôwr — firstbornNounmasculine singular construct
הַשְּׁבִ֔יhaš·šə·ḇîof the prisonerH7628 √ shᵉbîy — exiledArticleNounmasculine singular
הַשְּׁבִ֔י (H7628, shᵉbî) — "the captive," properly "exiled." Cambridge records the variation from 11:5 (there "the bondmaid that is behind the mill"); both phrases mean, in Pulpit's words, "all, from the highest to the lowest."
√ ʼăsher — who, which, what, thatPronounrelative
בְּבֵ֣יתbə·ḇêṯin the dungeonH1004 √ bayith — a house (in the greatest variation of applications, especially family, etcPreposition-bNounmasculine singular construct
הַבּ֑וֹרhab·bō·wr. . .H953 √ bôwr — a pit hole (especially one used as a cistern or a prison)ArticleNounmasculine singular
הַבּ֑וֹר (H953, bôwr) — "the pit," a cistern-prison; the lowest pole of the throne-to-pit merism that levels all Egypt under one judgment.
וְכֹ֖לwə·ḵōlas well as allH3605 √ kôl — properly, the wholeConjunctive wawNounmasculine singular construct
בְּכ֥וֹרbə·ḵō·wrthe firstbornH1060 √ bᵉkôwr — firstbornNounmasculine singular construct
בְּהֵמָֽה׃bə·hê·māhamong the livestockH929 √ bᵉhêmâh — properly, a dumb beastNounfeminine singular
בְּהֵמָֽה (H929, bᵉhêmâh) — "beast," properly "a dumb beast"; BSB "livestock." The plague extends to the firstborn of the animals (cf. 11:5), the sweep of the stroke reaching past humanity into the brute order.