STP stands for standard temperature and pressure, but it can also mean other things depending on the context. When referring to automotive maintenance, STP can mean oil and fuel additives, while in finance, it can stand for straight-through processing. In biology, STP can mean signal transduction pathway, and in communication and networking, it can stand for spanning tree protocol. Other synonyms for STP include normal conditions, benchmark, and default setting. It's important to understand the context in which STP is used to properly discern its meaning, and finding appropriate synonyms can help with clarity and understanding.