Answer: stairstep

AnswerCrossword Clue
STAIRSTEPUnit in a case
STAIRSTEPUnit between levels
STAIRSTEPRiser's place
STAIRSTEPPart of a flight.
STAIRSTEPPart of a flight
STAIRSTEPFlight unit
stairstepto carry out an exercise like stepping on a stair