An oxime is one in a class of compounds with the general formula R1R2NOH, where R1 is an organic side chain and R2 is either hydrogen, forming an aldoxime, or another organic group, forming a ketoxime.

Oximes can be formed by the action of hydroxylamine on aldehydes or ketones.

The term oxime dates to the 19th century, a condensation of the words oxygen and imide.