motive power
Concise Oxford English Dictionary © 2008 Oxford University Press:
motive power
▶noun
- 1 the energy (in the form of steam, electricity, etc.) used to drive machinery.
- 2 the locomotives of a railway system collectively.
'motive power' also found in these Oxford entries:
escapement
- heat engine
- motor
- nuclear power
- prime mover
- shaft
- shafting
- traction
- trailing wheel

