That cannot be assigned to a particular class or category; impossible to categorize.
unclassable/(ˌ)ʌnˈklɑːsəbl/ /(ˌ)ʌnˈklasəbl/ /(ˌ)ʌŋˈklɑːsəbl/
Mid 19th century; earliest use found in Frances Trollope (1779–1863), travel writer and novelist. From un- + classable.
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