粤 is the official one-character abbreviation for Guangdong — it appears on every Guangdong license plate (粤A is Guangzhou, 粤B is Shenzhen, etc.). It also forms the names of Cantonese culture: 粤语 (Cantonese language), 粤菜 (Cantonese cuisine), 粤剧 (Cantonese opera).
history
粤 originally referred to the ancient Baiyue (百越) peoples south of the Yangtze. Over time the region split into multiple provincial abbreviations, with 粤 narrowing to mean Guangdong specifically (Guangxi uses 桂).