Not a word, but instead a style of thread on Boards. The hashtag (#) is usually used before each line of a story on Boards to differentiate the experience and the actual content of the thread, this is where the Hashtag style gets its name from. Best example of something similar to this outside of Boards is 4chan's "greentext". Ironically enough, the hashtag style was actually first used by a 4channer who found boards and decided to convert a common greentext copypasta to a more Boards-friendly format.