From Middle English appel of the eie, from Old English æppel on the ēagan, used in biblical texts (Deuteronomy 32:10, Psalm 17:8; Proverbs 7:2, Lamentations 2:18, and Zechariah 2:8; compare the quotations) as a calque of Biblical Hebrew אִישׁוֹן עֵינוֹ (ʾîšôn ʿênô, “pupil of the eye”).

• (RP) IPA: /ˌæpl̩‿əv sʌmwʌnz ˈaɪ/
• (America) IPA: /ˌæp(ə)l‿əv sʌmwʌnz ˈaɪ/

apple of someone's eye

1. (idiomatic) The object of somebody's affections; a person (or sometimes a thing) that someone strongly prefers; a favourite, a loved one.

   Sara was never the same after losing her daughter, the apple of her eye.

   • 1535 October 14 (Gregorian calendar), Myles Coverdale, transl., Biblia: The Byble, […] (Coverdale Bible), [Cologne or Marburg]: [Eucharius Cervicornus and Johannes Soter?], →OCLC ↗, Psalm xvj:[8], folio xiiij, recto ↗, column 2:

     Kepe me as the apple of an eye, defende me vnder the ſhadowe of thy wynges.

     Psalm 17 in modern versions of the Bible.

   • 1584 (date written), Richard Hakluyt, “What Speciall Meanes may Bringe Kinge Phillippe from His Highe Throne, and Make Him Equall to the Princes His Neighboures; wherewithall is Shewed His Weaknes in the West Indies”, in A Particuler Discourse Concerning the Greate Necessitie and Manifolde Comodyties that are Like to Growe to this Realme of Englande by the Westerne Discoueries Lately Attempted, […]; published in Charles Deane, editor, A Discourse on Western Planting, […] (Collections of the Maine Historical Society, Second Series; II), Cambridge, Mass.: […] John Wilson and Son [for the Maine Historical Society], 1877, →OCLC ↗, page 59 ↗:

     If you touche him [Philip II of Spain] in the Indies, you touche the apple of his eye; for take away his treasure, which is neruus belli [the sinews of war], and which he hath almoste oute of his West Indies, his olde bandes of souldiers will soone be dissolved, his purposes defeated, his power and strengthe diminished, his pride abated, and his tyranie utterly suppressed.

   • 1611, The Holy Bible, […] (King James Version), London: […] Robert Barker, […], →OCLC ↗, Deuteronomy 32:9–10 ↗, column 1:

     For the Lords portion is his people: Jacob is the lot of his inheritance. He found him in a deſert land, and in the wasſe howling wilderneſſe: Hee ledde him about, he inſtructed him, hee kept him as the apple of his eye.

   • 1816, Jedadiah Cleishbotham [pseudonym; Walter Scott], chapter VII, in Tales of My Landlord, […], volume III (Old Mortality), Edinburgh: […] [James Ballantyne and Co.] for William Blackwood, […]; London: John Murray, […], →OCLC ↗, page 139 ↗:

     [P]oor Richard was to me as an eldest son, the apple of my eye, and my destined heir; but he died in his duty, and I—I— […] I live to avenge him.

• apple of the eye
• eye-apple

• French: prunelle de ses yeux
• German: Augapfel
• Portuguese: menina dos olhos
• Russian: свет очей
• Spanish: ojito derecho, niña de sus ojos