^ âeucatastropheâ (US) / âeucatastropheâ (UK) in Oxford Dictionaries, Oxford University Press.
For cooked onions, you can find one answer here: http://www.stilltasty.com/fooditems/index/17825. 1  3-5 days in the refrigerator. 2  refrigerate withing 2 hours of cooking. 3  refrigerate in covered container or wrap tightly with heavy-duty aluminum foil or plastic wrap.
Cut onions will be OK for a couple days in the fridge. If you are going to use it in cooking, chop the remainder of the onion when you first cut it up. Put it into a containerâ¦ and freeze. Then, you can take out what you need as you need it.   Another answer If kept in an airtight container 7 days.