Waste (wāst) v. 1. To use, consume, spend, or expend thoughtlessly or carelessly: For hours on end we laid waste beneath the plastered moon. 2. To cause to lose energy, strength, or vigor; exhaust, tire, or enfeeble: The tar wasted her lungs. 3. To fail to take advantage of or use for profit; lose: You wasted an opportunity to be with me. 4. a. To destroy completely. b. Slang. To ****; ******. The cigarettes wasted our relationship. 5. Garbage; trash. You had the audacity to choose to keep them than throw them in the waste basket. 6. Regarded or discarded as worthless or useless. You were a waste of my time.