Used other than figuratively or idiomatically: see step, down.
to step down carefully from a train
2
Idiomatic To resign or retire from an office or position of authority.
She now wants to be a Paris MP. But Fillon wants the same Paris seat when he steps down, after next year's election. Both have their eye on the main prize: running for Paris mayor in 2014.2011 December 14, Angelique Chrisafis, “Rachida Dati accuses French PM of sexism and elitism”, in The Guardian, archived from the original on 02 Jun 2022:
Late on the previous Friday (September 2), AWC had announced that Managing Director Phil Whittingham "has decided to step down with effect from September 15".2022 September 21, Mel Holley, “MPs debate Avanti West Coast future as MD departs”, in RAIL, number 966, page 14:
3
Figuratively To reduce gradually or incrementally.
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.1958 September 23, “Swindon's First Main-Line Diesel Locomotive”, in Railway Magazine, page 604: