I propose the idiom: time as units.
The use of certain words to measure time could be convenient for measuring amounts of grin. It follows nicely that one second of time is roughly equal to the measure of time for one grin to be produced. Therefore, one grin could also be known as one grin-second or simply one second of grin. Further, one minute of grin is 60 grin seconds. Fractions of a single grin idiomatically follow the same measurements of time: milliseconds, nanoseconds.
My 2 seconds.