E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Hard Up.
Short of money. Navoir pas de quibus. Up often = out, as, used up, worn out, done up, etc. Hard up = nearly out [of cash]. In these, and all similar examples, Up is the Old English ofer, over; Latin, s-uper; Greek, υε.