Involved in the detoxification of xenobiotics and in the activation of ester and amide prodrugs. Converts monoacylglycerides to free fatty acids and glycerol. Hydrolyzes of 2-arachidonoylglycerol and prostaglandins (By similarity). a carboxylic ester + H2O = a carboxylate + an alcohol + H(+) cocaine + H2O = benzoate + ecgonine methyl ester + H(+) 2-(5Z,8Z,11Z,14Z-eicosatetraenoyl)-glycerol + H2O = (5Z,8Z,11Z,14Z)-eicosatetraenoate + glycerol + H(+) H2O + prostaglandin E2 1-glyceryl ester = glycerol + H(+) + prostaglandin E2 H2O + prostaglandin F2alpha 1-glyceryl ester = glycerol + H(+) + prostaglandin F2alpha Monomer. Belongs to the type-B carboxylesterase/lipase family.