- Jacob, Francois Jacob - French biochemist who (with Jacques Monod) studied regulatory processes in cells (born in 1920)
--1 is a kind of biochemist
- Jacob - (Old Testament) son of Isaac; brother of Esau; father of the twelve patriarchs of Israel; Jacob wrestled with God and forced God to bless him, so God gave Jacob the new name of Israel (meaning `one who has been strong against God')
--2 is a kind of patriarch