An organic compound in which two carbon atoms are linked through an oxygen atom (C-O-C). An ether may be a product of the condensation of alcohols. Ether also refers loosely to diethyl-ether, a colorless, volatile, highly inflammable liquid used in industry and biomedical research, and historically important as an anesthetic agent. In vivo, ether acts similarly to alcohol and chloroform, but its stimulant action on the heart is much more marked. Ether is a rapidly diffusible stimulant. (NCI04)