More cap-like or more resembling a cap; comparative form of cappy.
From cap plus -y (making it resembling or full of caps) plus -er (comparative form), creating the comparative adjective meaning 'more cap-like.'
This word is rare enough that it's almost never used, but if a linguist needed to compare which of two objects is more 'hat-like,' cappier is the technically correct English way to say it!
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