step-down

Deverbal from step down.

step-down (not comparable)

1. That decreases in stages.
2. (of a transformer etc.) That reduces a voltage.
   • 1958 September, “Swindon's First Main-Line Diesel Locomotive”, in Railway Magazine, page 604:

     The internal lighting of the new locomotives can be supplied either from the battery or the dynostarter, and may also be connected to an external supply of 200-250 volts a.c. through a changeover switch and a step-down transformer.

• step-up

• step down

• stew pond, stewpond, downstep