Isaac

noun

ˈī-zik

-zək

in the Bible : the son of Abraham and father of Jacob according to the account in Genesis

Word History

Etymology

Late Latin, from Hebrew Yiṣḥāq

First Known Use

before the 12th century, in the meaning defined above

Time Traveler

The first known use of Isaac was before the 12th century

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Cite this Entry

Style

“Isaac.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Isaac. Accessed 3 Nov. 2025.

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