Adults have adult circumstances.
The police must take all circumstances into account.
Samantha explained the circumstances behind her inability to pay for using Wanikani.
The feeling of the actions going on around you are the circumstances. For example: you feel like things are going pretty poorly right now, which is why the circumstances are looking pretty dire for you.
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.