m
• Adam is the name used in the opening chapters of the Book of Genesis for the first man created by God, but it is also used in a collective sense as "mankind" and individually as "a human".
Why should she lend me money? She doesn't know me from Adam. After working at the company for nearly ten years, and Jake's boss still didn't know him from Adam.
Origins
• In terms of dating, almost nothing is known about this phrase's origins except that it is likely an Americanism.
• In 1848 the author of a book on 'Nantucketisms' recorded a saying then in use on that island, 'Poor as God's off ox,' which, he said, meant very poor.
off ox
• The off ox was the one on the off-side of the vehicle. • This ox would be the farthest from the driver. • It appears to more strongly emphasize just how much you don't know about the person.
Not know someone from Adam
Meaning: To have never met someone and not know anything about them The form commonly used is 'not to know one from Adam's off ox'. Example: