'non-Yank' originates from English, specifically combining the prefix 'non-' (from Latin 'non', where 'non' meant 'not') with 'Yank' (a shortened form of 'Yankee').

'non-Yank' developed by attaching the negative prefix 'non-' to 'Yank'. 'Yank' is a clipped form of 'Yankee,' a term from the 18th century; 'Yankee' may derive from Dutch 'Janke' or a diminutive of 'Jan' (e.g. 'Jan Kees'), and it entered American English as a name for New Englanders before widening in use to mean Americans in general.

Initially it simply meant 'not a Yank' (i.e., not American). Over time it has remained largely the same in meaning but is used informally and can carry neutral or mildly contrasting/colloquial nuance depending on context.