The quality, condition, or characteristic of being east or eastern in direction or nature.
From 'east' + '-ness' (Old English suffix creating abstract nouns from adjectives). This follows the productive pattern in English of converting directional or qualitative words into nouns representing their essential quality.
The '-ness' suffix is one of English's most prolific word-building tools, but 'eastness' is rare because we typically don't philosophize about the 'easterness' of things—we just say 'it's in the east.' It shows how English can theoretically make abstract nouns from almost anything.
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