Answer
Definition: A compound with an oxygen bonded between two alkyl (or aromatic) groups; R-O-R.
Example: Diethyl ether $CH_3CH_2-O-CH_2CH_3$
Work Step by Step
Ethers are composed of two alkyl groups bonded to an oxygen atom. The general formula for an ether is R-O-R'. (The symbol R' represents another alkyl group, either the same as or different from the first.)
Example: Diethyl ether $CH_3CH_2-O-CH_2CH_3$