1.3 to spare (somebody) from effort, or from something undesirable
2.1 (transitive) to store for future use
Let's save the packaging in case we need to send the product back.
2.2 (transitive) to conserve or prevent the wasting of
Save electricity by turning off the lights when you leave the room
2.5 (intransitive) to economize or avoid waste
2.6 (transitive and intransitive) to accumulate money or valuables