NEAT (non-exercise activity thermogenesis)
NEAT is all the energy you spend moving that is not deliberate exercise: walking to the shop, fidgeting, standing, carrying things, pacing on the phone. It varies enormously between people and is the main reason two people with the same workout routine can have very different daily expenditure.
Example
NEAT is the part of an activity multiplier that is hardest to guess, which is why the multipliers are a convention rather than a measurement.