STI, the acronym for sexually transmitted infection, is a widely used term for diseases transmitted through sexual activities. However, there are many synonyms that can be used instead of STI. Some of the common synonyms include sexually transmitted disease (STD), venereal disease (VD), sexually transmitted infection/disease (STI/STD), and genitourinary infection (GUI). Other synonyms for STI are sexual infections, intimate infections, and reproductive infections. It is important to note, however, that these terms do not necessarily refer to the same diseases, but they are often used interchangeably in everyday conversations. Regardless of the synonym, it is essential to practice safe sex to reduce the risk of contracting or spreading infections.