Gabardine is a densely woven fabric in twill weave, and therefore is generally more supple than fabrics in plain weave.

'Gabardine' probably comes from the old Spanish word tavardina which was used in the Middle Ages for a coarse coat fabric. Coats are still being made of it, just think of the Burberry trench coats, but coarse the fabric isn't anymore, and the lighter types, of which you'll find a few here, are suitable for all kinds of other garments.