E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Do.
A contraction of ditto, which is the Italian détto (said), Latin dictus.
1
How do you do? i.e. How do you fare? It should be, How do you du! (Anglo-Saxon, dug-an = valre); in Latin, Quomodo vales.
2
Well to do. This, again, is not the transitive verb (facre) but the intransitive verb (valre), and means well to fare. (Anglo-Saxon, dug-an = valre.)
3
To do him, i.e. cheat or trick a person out of something.
4
I have done the Jew, i.e. over-reached him. The same as outdo = excel.