Postal abbreviation for Oxfordshire

(after a qualification) University of Oxford, used especially following post-nominal letters indicating status as a graduate.

Glyoxylic acid.

(organic chemistry) Any canonical form of a carbocation having the positive charge on an oxygen atom

(organic chemistry) A saturated, four-membered heterocycle containing two carbon atoms, one oxygen atom and one nitrogen atom; any derivative of this compound

(organic chemistry, especially in combination) Any alkyl group in which a methylene group has been replaced by a carbonyl group.

(organic chemistry) Any amide of a ketocarboxylic acid

(mineralogy) Containing oxygen.

plural of oxoanion

(chemistry) Any anion derived from an oxoacid