Factor
Cause, Key Factor
noun
So you need to know the cause for something, huh? Better start examining all the factors, then. There could be all sorts of contributing causes.
要因 is a relatively formal word that refers to something that leads to a result. It's often used in explanations or analyses to describe key contributing causes, especially when breaking down why something happened, like 成功の要因 (the key factors behind success).
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
主な要因は何ですか？
What is the main factor?
この問題には多くの要因がある。
There are many factors behind this issue.
仕事が大きなストレス要因になっているんです。
Work is a major cause of stress.
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