hardest button to button
Button: Noun - That round thing you find on your shirt to help keep it closed so all the perverts don't get a free look at my, your, our ample cleavage.
Button: Verb - "To Button" is to button something closed, like the shirt.
Hardest Button to Button = A button that, for some reason, just can't be buttoned easily. Possibly the button is to large for the eyelet, or it is just broken.
and yes, that was the UberCool literal version of it
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