Stands for poly-urethane laminate which is a special coating applied to fabric to make it water resistant. Depending on the coating, the fabric will either be breathable or non-breathable . Although the breathable aspect of the fabric means air can circulate, it doesn't mean you will be able to draw in enough air to fill your lungs and breathe if you hold it over your own mouth or nose.
Polyurethane laminate. Fabric that has been laminated with PUL is waterproof. The fabric that has been laminated can vary in weave (knit or woven) and material (cotton or polyester).
or Polyurethane Laminate, usually laminated to polyester this is the waterproofing material of most breathable wraps.
Abbreviation for polyurethane laminate, which is simply knit fabric that has a waterproof laminate applied to the back. Laminated polyester (usually your PUL solid colors) resists moisture, while laminated cotton blends (usually your PUL prints) wick moisture quicker and require more frequent diaper changes.
Waterproof material used on most breathable wraps or AIOs.