ef·flux·ion \eˈfləkshən, ə̇ˈ-\noun (-s) Etymology: Late Latin effluxion-, effluxio act of flowing out, from Latin effluxus + -ion-, -io -ion : efflux — used especially of time < mere effluxion of time has given him a long range of observation > < his term of office expired by effluxion of time previously fixed >