There's not an easy way to "export" them but if you find the industry property under settings>properties it should show you the attributes for it including the options already defined.
I had the same issue. I painstakenly copied and pasted all the industries listed in Hubspot in to an Excel spreadsheet so that I could more easily update my Excel database before uploading to Hubspot. This list was created on August 31, 2019. Hope this is helpful!
Thanks for taking the time to export and post this list; it was the info I needed at the exact time I needed it; hope I can do the same for someone in 2020.
There's not an easy way to "export" them but if you find the industry property under settings>properties it should show you the attributes for it including the options already defined.