simmer
verb uk/ˈsɪm.ər/ us/ˈsɪm.ɚ/
[ I or T ]炖，煨
to cook something liquid, or something with liquid in it, at a temperature slightly below boiling
Leave the vegetables to simmer for a few minutes. 把蔬菜再炖几分钟。
[ I ]（分歧或消极情绪）酝酿，积聚
If a disagreement or negative emotion simmers, it grows slowly stronger over a period of time and could become more serious at any moment.
The strike has been simmering for weeks. 罢工已酝酿了数周。
She's been simmering with resentment ever since the meeting. 会议之后她便心生怨恨，一直耿耿于怀。
Phrasal verb
simmer down （怒火或激动的情绪）平息，冷静下来，平静下来
to become less angry or excited about something
Come on kids! Simmer down and get on with your work! 快点儿，孩子们！安静下来开始做功课！