Muslin, plain-woven cotton fabric made in various weights. The better qualities of muslin are fine and smooth in texture and are woven from evenly spun warps and wefts, or fillings. They are given a soft finish, bleached or piece-dyed, and are sometimes patterned in the loom or printed. One of the favorite baby necessities is a muslin swaddling blanket. They are lightweight, oversized, and super soft. swaddling blankets are made with organic cotton muslin, are great quality, and get softer with every wash.