The quality of being ambient; the surrounding or enveloping nature of something, especially atmosphere or environment.
From Latin ambiens (going around, surrounding) + -cy suffix. This is a more technical or formal variant of ambience, sometimes used in scientific or philosophical contexts.
Ambiency is a word that sounds like it should be common but almost never appears in modern English—it's one of those linguistic 'roads not taken' where French ambiance won out as the preferred term.
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