promissive
From LSJ
ἄλογον δὴ τὸ μήτε μάχης ἄρξασθαι μήτε τοὺς φίλους φυλάξαι, ἐὰν ὑπό γε τῶν βαρβάρων ἀδικῆσθε → It is irrational neither to begin battle nor to guard the friends, if you are ever wronged by the foreigners
Latin > English (Lewis & Short)
prōmissīvē: adv., v. promissivus.
Latin > French (Gaffiot 2016)
prōmissīvē, sous forme de promesse : Tert. Marc. 5, 10.