The term "grapevine reports" is often used in reference to rumors or gossip that spreads through informal channels and can be unreliable. However, there are several other synonyms for this phrase that can convey a similar meaning. For example, the phrase "word on the street" implies that information is spreading through informal channels. "Scuttlebutt" is a nautical term that refers to rumors spreading onboard a ship. "Whispers" and "murmurs" are also common synonyms for grapevine reports. Regardless of the terminology used, it's important to critically evaluate the accuracy and credibility of any information received through informal channels, as it can be easily distorted or exaggerated.