Twill/twɪl/ Definition 1 of 2Pro Tip 1/3Durability Association Twill is known for its strength, commonly used in clothing that requires durability. My new twill jacket is sturdy enough for hiking. Pro Tip 2/3Distinctive Diagonals Twill is easily identified by its visible diagonal lines on the fabric surface. You can recognize the twill pattern on these jeans. Pro Tip 3/3Fashion Preference Twill fabric is often preferred for its aesthetic appeal and draping quality. My designer prefers working with twill for its elegance.