2. An object frequently used as a gem which is formed within the shell of a bivalve or mollusk as the result of the production of layers of secretion which encase an irritating foreign object and is often colored and lustrous: Aurora discovered a pearl in an oyster while she was eating some of them at dinner.
3. A gem which is made from the covered irritant in a bivalve: Francisca wore a necklace of a large pearl and earrings with a beautiful pearl on each one.
4. Something that is cylindrical and luminescent: Dew drops, each one of which was like a pearl, were glistening on the blades of grass as the sun came out.
Dennis could hear the gentle purl of the birds as they were settling in the bushes for the night.2. A stitch used in knitting, often used in conjunction with a knit stitch to create a smooth surface: Marina's teacher recited "knit one, purl one", in hopes that she would learn to knit properly.
When Andrew's aunt was knitting a jacket, she used the "knit one, purl one" pattern.
Before she was done, she decided to purl a lovely design on the sleeves, including the pearls which she had from a broken necklace.