An archaic or variant form of 'easterly'; situated toward the east or blowing from the east.
From 'eastern' plus '-ly' (in the manner of/resembling). This is an older or dialectal variant of 'easterly,' less common in modern English.
English had multiple ways to form directional adjectives—'-erly' (easterly) and '-ern-ly' (easternly)—but speakers preferred '-erly' as more efficient, showing how efficiency drives language change.
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