smut/porn/erotic is sexually explicit material or pornographic writing; this could refer to a small portion of a story, or in its entirety. historically, the terms "lemon" (i.e porn) and "lime" (i.e erotica) were euphemisms used to allude to explicit material. they were in common use in the 2000s, but have since outdated terms that waned in usage. however, as of december 2018, the terms have seen a revival due to tumblr's censorship on adult content. the use of the terms lemon and lime allow writers to circumnavigate the "explicit terminologies" tumblr banned, while still tagging their work as explicit.