1 definition by Coolest girl or person ever

Making this up basically, doing something for 7 days and 8 nights (you know 7 days a week 8 nights a week) and it could be just a Change in your life like waking up early or eating healthy like a summer goal.
Girl 1: hey starting tomorrow I'm gonna do my 7/8 day! I'm so excited!
Girl 2: really what's your resolution for 7/8 day?
Girl 1: eating healthy!
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