donatio propter nuptias → ἕνεκα γάμου δωρεά, δωρεά ένεκα γάμου

[spiros]

donatio propter nuptias → προγαμιαία δωρεά, πρὸ γάμου δωρεά
donation after marriage, dowry


DONATIO PROPTER NUPTIAS. The meaning of this term is explained in the Institutiones (2.7 §3). It was originally called Donatio ante nuptias, because it could not take place after the marriage; but when it was made legal to increase the donatio after marriage, and even to constitute it altogether after marriage, the more comprehensive term donatio propter nuptias was used
LacusCurtius — Smith's Dictionary of Greek and Roman Antiquities

Donatio Propter Nuptias - Oxford Reference

[billberg23]

Since propter means "by reason of," and in view of the above English explanation of the term ("the more comprehensive [i.e. than 'before' or 'after'] term donatio propter nuptias was used"), would something like  επ' ευκαιρία γάμου be more appropriate than πρὸ γάμου? 

[spiros]

Master, I followed the gloss in the Oxford link above (not sure why they used circumflex for "προγαμιαία").

I guess πρό can also denote motive:

(of cause or motive) for, out of, from
πρό - Wiktionary

[billberg23]

Oxford boys are not always trustworthy.  (-:

[spiros]

Indeed, another suggestion: ἕνεκα γάμου δωρεά
Themis, ē exetasis tēs Hellēnikēs nomothesias - Βιβλία Google