ˈestə(r) noun
( -s )
Etymology: German, from essigäther acetic ether, from essig vinegar (from Old High German ezzīh, from Latin acetum ) + äther ether, from Latin aether — more at acetic , ether
: any of a class of compounds (as ethyl acetate, triphenyl phosphate) that on hydrolysis yield an organic or inorganic acid and an alcohol or phenol and hence may be classified either by their acid constituent (as benzoic esters or nitric esters) or by their alcohol or phenol constituent (as methyl esters or tolyl esters) and that are usually fragrant liquids if sufficiently volatile, esters of carboxylic acids characterized by the group −COOR being found in essential oils and synthesized especially for use in artificial fruit essences — see glyceride , polyester , wax 2a; compare acylal