waste

Which Means:

To use only a little bit of and throw the rest away. (Homonym of 'waist')

Nathan was careful not to waste any paper in making his project.

'Waste' can also be a noun meaning what is thrown out or not used: You can make a difference in the environment and not create much waste.

The area around the middle of your body, above your hips and below your ribs. (Homonym of 'waste')

Corsets during the Middle Ages were fashionable, making women have small waists.

To remember how to spell 'waist', maybe you can think that 'I' have a 'waist'.