In chemistry (particularly organic chemistry), methoxy refers to the functional group consisting of a methyl group bound to oxygen. This alkoxy group has the formula O–CH3.
The word is used in organic nomenclature usually to describe an ether. It is also an electron-donating group and can cause an organic compound to become less acidic.
The simplest case is another methyl group giving dimethyl ether; other methoxy ethers are methoxyethane and methoxypropane. In the field of natural compounds, examples bearing methoxy groups are O-methylated flavonoids. It is also found in Mescaline and its analogues, 2C-B, 2C-E and 2C-P for instance.