'Anglo-Saxonish' originates from the compound 'Anglo-Saxon' plus the adjectival suffix '-ish'. 'Anglo-Saxon' itself names the Angles and Saxons (Germanic peoples) and the culture/language descended from them, while '-ish' forms adjectives meaning 'having the quality of'.

'Anglo-Saxonish' developed by attaching the Old English/Proto-Germanic-derived suffix '-ish' (from Old English '-isc') to the modern compound 'Anglo-Saxon'. 'Anglo-Saxon' came into English from the names of the tribes 'Angle' and 'Saxon' (Old English 'Engl' and 'Seaxe'), referring to early medieval inhabitants of England; the combined compound 'Anglo-Saxon' became standard in Middle English and later.

Initially, the components referred specifically to the peoples 'Angles' and 'Saxons' and their immediate cultural-linguistic identity; the adjectival formation has steadily been used to mean 'having the qualities of' those peoples or their language, and 'Anglo-Saxonish' retains that descriptive sense.