An enzyme that reversibly transfers an acyl residue from a lecithin to cholesterol, forming a 1-acylglycerophosphocholine (a lysolecithin) and a cholesteryl ester; a deficiency of this enzyme leads to accumulation of unesterified cholesterol in plasma resulting in anemia, proteinuria, renal failure, and corneal opacities; LCAT is also low in people with fish eye disease. SYN: lecithin acyltransferase.