An informal or dialectal term, possibly referring to something deemed or judged; a variant or colloquial diminutive related to 'deem.'
This appears to be a dialectal or informal formation from 'deem' with a diminutive suffix '-ie' or '-y,' similar to how British English creates informal nicknames. The term is quite rare and regional.
Deemie is so obscure that it might be one of those beautiful dead-end words—a playful formation that existed in someone's dialect or community but never quite caught on widely enough to survive in standard dictionaries, representing how language is constantly experimenting.
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