1. To pass a certain amount or period of time by being very lazy, languid, or idle. In this usage, a noun or pronoun can be used between "moon" and "away." Too many kids just moon the summer away in front of their computers or televisions. In my 20s, I would spend every Friday and Saturday night at the bar with my friends, but now that I have kids, I just want to moon away the evenings at home in front of the TV.

2. To pass a certain amount or period of time by desiring, yearning for, or grieving over someone or something in an intense, melancholy way. You can't just coop up in here and moon the weekend away because of one bad breakup! Now get dressed—you're coming with us for a night on the town! I lived in Japan for two months on an exchange trip, and when I came home I mooned away the rest of the summer wishing I could go back.