More grey; having a greater degree of grey color than something else being compared.
Comparative form of 'grey' (or 'gray'), formed with the suffix '-er.' In American English 'grayer' is standard, while 'greyer' is the British English preferred form.
The grey/gray spelling divide between British and American English is one of the most consistent patterns Noah Webster introduced, and you can track it historically through his dictionary to see when the preference shifted.
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