The name "Gilbert" means "bright pledge", derived from the Germanic elements gisil "pledge, hostage" and beraht "bright". The Normans introduced this name to England, where it was common during the Middle Ages. It was borne by a 12th-century British saint, the founder of the religious order known as the Gilbertines.
Whimple is a village in Devon, near Exeter, where J. K. Rowling went to university. This could be a link to Wimple, as there are other references to places in the area in the books.