Quilted apparel fabric refers to fabric that has been stitched or quilted together with padding or batting in between. It is commonly used for making garments such as jackets, vests, coats, and other outerwear. 

When purchasing quilted apparel fabric, you can typically find it sold by the yard. This means that you can order the fabric in continuous lengths, depending on your specific needs.

There are different types of quilted fabrics available, including:

1. Pre-quilted fabric: This type of fabric is already quilted before you purchase it. It saves you the effort of quilting the fabric yourself. Pre-quilted fabric can come in various patterns, designs, and thicknesses, offering a ready-made quilted look for your projects.

2. Double-sided quilted fabric: This fabric has quilted patterns on both sides, allowing for reversible designs. It is often used when you want both sides of your project to have a quilted appearance.

3. Pre-quilted fabric by the yard: This refers to pre-quilted fabric that is sold in increments of one yard. You can order as many yards as you need to complete your project.

If you are specifically looking for pre-quilted Christmas fabric, you may be able to find options that feature festive patterns, motifs, or holiday-themed designs. These fabrics can add a touch of seasonal cheer to your quilting or apparel projects during the Christmas season.

When purchasing quilted fabric, it is advisable to check the product descriptions or reach out to the seller or fabric supplier to ensure that you are getting the specific type, design, and yardage of fabric you desire for your project.