名詞 externality:

1. the quality or state of being outside or directed toward or relating to the outside or exterior
   同義詞：outwardness

ex.ter.nal.i.ty

n.（名詞）
【復數(shù)】 ex.ter.nal.i.ties
The condition or quality of being external or externalized.
客觀性：客觀的或使客觀化的條件或性質(zhì)

Something that is external.
外部事物
An incidental condition that may affect a course of action:
外部因素：可能影響行動的進程的偶然條件：
例句：
.Our economic system treats environmental degradation as an externality—a cost that does not enter into the conventional arithmetic that determines how we use our resources.(Barry Commoner)
.我們的經(jīng)濟系統(tǒng)作為外部偶然因素引起環(huán)境的退化——這個沒有列入常規(guī)計算的價值決定我們?nèi)绾卫梦覀兊馁Y源.(巴里·康芒納)