The term 'Lay a Lawn On' is a job description for landscaping. It involves the use of two materials: TEM, which stands for Turf Establishment Mat, and SOD, which stands for SOD. TEM is a biodegradable mat made of coconut fibers that helps to establish a lawn by providing a layer of protection and insulation for the soil and grass seed. SOD is a type of grass that is cut into squares and laid on top of the TEM to create a lawn. Together, these two materials help to create a lush, green lawn.