1 change, alter, diversify, transform, reshape, remodel, restyle, modify, reorganize:
We vary the programme each month to make it more interesting.
2 change, switch, alternate, fluctuate, vacillate:
The manager's attitude varies from helpful to downright rude.
3 depart, deviate, differ, diverge, shift, veer:
These results do not vary from the average by more than five per cent.