Salvete! Are the words “olim” and “quondam” interchangeable or is there some funny Latin rule for their use? From my books it seems they are interchangeable,however,my books don’t discuss the rules for their usage and I need to be 100% certain that I am using them correctly before I begin using them in speech and teaching them to my son. Thank you in advance for any help.
olim - at that time, some time ago, once upon a time, once, formerly, of old, “one day”
quondam - at some time, at one time, once, heretofore, formerly, on a time
olim seems to be more specific but also has a future sense. quondam doesn’t seem to do that at all. I can’t tell you for certain when to use them, as I too am a beginner, but that might help you.
I would have said the opposite, that quondam implies greater definiteness than olim. At any rate, both can be used of the future as well as of the past, and even of the present, in the sense of ‘sometimes’ or ‘at certain times’. The main difference between the two, IMHO, is that olim, when used of the past, means something like ‘of old’, whereas quondam can refer to the recent past as well.
Thus, quam olim Abrahae promisisti, et semini ejus.