Where does “pros ton kairon” come from?

pros ton kairon (English) comes from Ancient Greek πρὸς τὸν καιρόν.

Ancestry of “pros ton kairon”, step by step

Step	Language	Word	Meaning
1	Ancient Greek	πρὸς τὸν καιρόν	—

pros ton kairon — Etymology, Origin & Word History | Etymology Explorer