The Fire emoji is commonly used to praise someone or something, signifying that a person, object, album, movie, or so on, is “lit,” a slang term to describe something that is exceptionally cool or great.
But, lit has other meanings too . . . and, of course, that means so does the Fire emoji. As lit is also slang for “intoxicated,” the Fire emoji doubles as a way to say someone is very high or wasted. The term fire has been used as slang for high-quality weed in hip-hop since the early 1990s, and so sometimes the Fire emoji is used to reference marijuana, too.