What did Catherine of Aragon wear on her head?

Catherine of Aragon wore a gable hood, named after the gable of a house. it had a pointed top and stiff flaps which framed the face. The length of the sides of a gable hood, sometimes called a spanish hood, changed over time; however in Catherine of Aragon's time, they were typically slightly longer than past the jaw with flared ends. Gable hoods had fabric in front which covered the hair in front and Catherine of Aragon often had a covering on the back of her hood to cover her hair, which was adopted by the rest of court and other fashionable ladies.

an Excellent image depicting this can be found on the related link below.