A sunshade is something you put between yourself and the sun to make shade. The old-fashioned meaning is the one dictionaries lead with: a light umbrella carried, especially by women a hundred years ago, to keep the sun off — the thing you see in old paintings, also called a parasol. But the word is still alive for other things that do the same job: the big umbrella over a café table, an awning over a shop window, and, very commonly today, the folding silver screen you put inside a car windscreen so the seats do not turn into an oven. Car shops in Taiwan sell exactly this. So do not think of the word as dead — think of it as an old word that has quietly moved into new jobs. It is countable: a sunshade, two sunshades.

遮陽傘、遮陽板；車用的那種叫遮陽板／遮陽簾