The quality or state of being overly stubborn, unreasonably eccentric, or having strange and unpredictable opinions and behaviors.
From 'crotchet' (a perverse notion or whim, from Old French crochete, a hook), with the suffix '-iness' creating an abstract noun of the quality.
A crotchet is literally a hook-shaped stitch in crochet, but it came to mean a twisted or 'hooked' idea—old people muttering about their peculiar beliefs became known for their 'crotchetiness,' which is probably why we associate being quirky with being stubborn.
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