XL is the clothes size that means extra large — bigger than L (large). You see it printed on the label inside a shirt, on the tag in a shop, and in the size list on a shopping website: S, M, L, XL, XXL. It is usually written in capitals with no full stops, and you say the two letters: "ex-el". You can use it on its own ("Do you have this in XL?", "I take an XL") or before the noun ("an XL T-shirt"). For sizes above it, English piles up the X's: XXL, XXXL, or written 2XL, 3XL. Two useful facts for shopping. One, XL is not a fixed measurement — an XL from an American brand is often much bigger than an Asian XL, which is why Taiwanese shoppers looking at Japanese or Taiwanese labels may need a size up when buying from the US. Two, the letters have escaped clothing: fast-food drinks, pizza, phone screens and cars all get called XL to mean "the big one", and companies use it in product names for the same reason. Notice you say "an XL", not "a XL", because the letter X begins with a vowel sound, /e/.