Jacob

American  

[jey-kuhb, zha-kawb] / ˈdʒeɪ kəb, ʒaˈkɔb /

noun

1. (in the Bible) the second son of Isaac, the twin brother of Esau, and father of the 12 patriarchs.

2. François 1920–2013, French geneticist: Nobel Prize in Medicine 1965.

3. a male given name: from a Hebrew word meaning “supplanter.”

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Jacob British  

/ ˈdʒeɪkəb /

noun

1. Old Testament the son of Isaac, twin brother of Esau, and father of the twelve patriarchs of Israel

2. Also called: Jacob sheep.  any of an ancient breed of sheep having a fleece with dark brown patches and two or four horns

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Jacob Scientific  

/ zhä-kôb′ /

1. French geneticist who studied how genes control cellular activity by directing the synthesis of proteins. With Jacques Monod, he theorized that there are genes that regulate the activity of other, neighboring genes. They also proposed the existence of messenger RNA.

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Etymology

Origin of Jacob

sense 2 in allusion to Genesis 30:40

Example Sentences

“There is nothing you can do in this courtroom,” she said, “that can bring Mark and Jacob back.”

From Los Angeles Times • Jun. 10, 2026

After quitting his semiconductor-engineering job last year, 35-year-old Jacob Keeton left his hometown of Beaverton, Ore., and embarked on a 12,000-mile road trip across America and back.

From MarketWatch • Jun. 10, 2026

In each market mania, new celebrity stock pickers get anointed, from Ryan Jacob and his Internet Fund during the dot-com era to Cathie Wood and her ARK Innovation ETF during the pandemic rally of 2020.

From The Wall Street Journal • Jun. 8, 2026

Mark and Jacob Iskander were with their mother and younger sibling in a crosswalk at Triunfo Canyon Road when witnesses say the two cars came speeding toward them.

From Los Angeles Times • Jun. 6, 2026

Notably, Brenner and Jacob later discovered the messenger RNA was a facsimile of the DNA chain—a copy made from the original.

From "The Gene" by Siddhartha Mukherjee