Skein/skeɪn/ Definition 1 of 3Pro Tip 1/3Crafting Context Used often in crafting hobbies; not to be confused with a finished product. Can you hand me that green skein? I'd like to crochet a beanie. Pro Tip 2/3Unwound Yarn A skein is yarn not yet wound into a ball and may become tangled if not handled carefully. She laid the skein out before winding it to avoid knots. Pro Tip 3/3Visualize Shape Imagine a loosely coiled bundle or a thick braid to visualize a skein of yarn. The skein looked like a bundle of twisted silk.