if you cut off the top of an onion & leave it in the frigde overnight can it be used?
Answer:
Yes. The halachic problem with leaving an onion overnight applies specifically when it has been completely peeled. If some of the peel remains, and certainly if only the top has been cut off, there is no problem.
See Rambam (Rotze’ach 11:5); Shulchan Aruch, Choshen Mishpat 427:9-10; Shulchan Aruch Ha-Rav, Shmiras Ha-Guf 4.
For part of the peel, see also Divrei Yatziv Yoreh De’ah 31.
Best wishes.
