Isaac · Daily fortune

Isaac is a masculine name of Hebrew origin meaning "he will laugh, he will rejoice", from the Hebrew name יִצְחָק (Yitsḥaq), which Behind the Name derives from the verb צָחַק (tsaḥaq), "to laugh". Genesis ties the name to laughter twice: Abraham laughed when God said his aged wife Sarah would bear a son, and Sarah laughed when she overheard the same prophecy. Isaac became the father of Esau and Jacob and is one of the three patriarchs of the Hebrew Bible, used as a given name among Jews, Christians and Muslims. In English it was occasional in the Middle Ages, more common among Jews, and spread after the Reformation. It ranked #47 for American boys in 2025.

Behind the Name gives Isaac as "from the Hebrew name יִצְחָק (Yitsḥaq) meaning 'he will laugh, he will rejoice', derived from צָחַק (tsaḥaq) meaning 'to laugh'". It adds that "the Old Testament explains this meaning, by recounting that Abraham laughed when God told him that his aged wife Sarah would become pregnant with Isaac (see Genesis 17:17), and later Sarah laughed when overhearing the same prophecy (see Genesis 18:12)". Wikipedia gives the same origin, describing Isaac as transliterated from Yitzhak or Yitzchok (Hebrew יִצְחָק) and glossing it "(he) will laugh". The two sources agree and neither records a competing derivation, so the meaning is treated as established. The related name Abraham is glossed by Behind the Name as "father of many".

Isaac is one of the three patriarchs of the Hebrew Bible, and his story is told in Genesis. Behind the Name summarises it: when Isaac was a boy, God tested Abraham's faith by ordering him to sacrifice his son, though an angel prevented the act at the last moment; Isaac went on to become the father of Esau and Jacob with his wife Rebecca. Wikipedia notes that the name is derived from Judaism and has been a given name among Jewish, Christian and Muslim societies. Its English career was slow: Behind the Name says that "as an English Christian name, Isaac was occasionally used during the Middle Ages, though it was more common among Jews", and that "it became more widespread after the Protestant Reformation". The name's best-known modern bearers, the physicist Isaac Newton (1643–1727) and the science-fiction writer Isaac Asimov (1920–1992), are cited by both sources; Wikipedia adds figures from the sixteenth-century Kabbalist Isaac Luria to the current Israeli president Isaac Herzog.

Isaac ranked #47 for boys in the United States in 2025 according to the Social Security Administration. Neither Behind the Name nor Wikipedia gives historical ranking data for the name, so no trend can be stated from the sources consulted; the note that it "became more widespread after the Protestant Reformation" is the only historical usage statement available. Behind the Name lists Isaac as in current use in English, Spanish, Portuguese, Catalan and French as well as in Jewish and biblical contexts, and Wikipedia records equivalents in more than 80 languages, so the name is in wide international use even though only the American figure is documented here.

English Isaac is /ˈaɪ.zək/, EYE-zək, with a long I and a voiced Z. The name is used in its English spelling across Spanish, Portuguese, Catalan and French too: Behind the Name gives Spanish /i.sa.ˈak/ (three syllables, stress on the last) and French /i.zak/ or /i.za.ak/. Other languages use their own forms, listed below from Behind the Name; pronunciations other than the English, Spanish and French ones were not verified in this pass.

Isaac has the weight of a patriarch's name without the heaviness: the meaning is about laughter, the sound is bright and open, and the two famous modern bearers, Newton and Asimov, give it a scholarly, scientific glow. It fits the current taste for Old Testament boys' names that feel classic rather than churchy, sitting beside Ezra, Eli and Levi in style, and it has a built-in old-fashioned nickname in Ike for parents who want one. Unlike Jacob it never had a #1 run in the United States, so it reads as steady rather than dated. The double-A spelling is the one trap: Behind the Name records Issac as an English variant, which looks like a by-product of people misplacing the second A, so a child named Isaac can expect to spell it out occasionally. Against that, the name is easy to say, ends in a soft consonant that pairs well with almost any surname, and is recognisable in the same spelling from Madrid to Montreal, since Behind the Name lists it as current in Spanish, Portuguese, Catalan and French as well as English.

Isaac's namesakes are unusually distinguished in science and letters. The bearers below are the ones named in the Behind the Name entry and the Wikipedia article consulted for this profile.

Names that share Isaac's Old Testament roots, its bright initial-vowel sound, or its relatives from the same Genesis story.