A Lawyer weighs in:
From the Loeb.
A grammarian has a go:
Again from the Loeb.
And now we get to the passage I actually went looking for:
So still from the Loeb.
Sesterce as a translation of nummo is weird and uncalled for. A medimnus = 6 modii.
Cf. Cicero, Verrines 2.3.116
Verum ut hac ipsa ratione summam mei promissi compleam, ad singula medimna multi HS binos, multi HS singulos semis accessionis cogebantur dare, qui minimum, singulos nummos.
But that by this present calculation I may make out the sum which I promised to do, many were compelled besides to pay two sesterces, and many one and a half, with each medimnus, and those who had to pay least paid a single coin with every medimnus.
I want to check out the manuscripts but it seems like nummos here must mean sestertius. So maybe it should mean a single unit rather than a physical coin. …
Here is Varro’s vocabulary (again Loeb):
I think in the end it was this passage I was truly looking for…