street gossip; idle rumors; town talk
A yojijukugo (four-character compound) referring to unverified talk and rumors circulating among ordinary people. Literary and somewhat formal; not used in casual conversation.
It is important to verify the facts without being misled by street gossip.
噂 is the common word for 'rumor' or 'gossip' in everyday speech. 街談巷説 is a formal, literary yojijukugo with a similar meaning but used in more elevated or written contexts.
風説 also means 'rumor' or 'hearsay' and is more formal than 噂, but less literary and less specific to street-level talk than 街談巷説.
A yojijukugo composed of 街 (town), 談 (talk), 巷 (alley), and 説 (theory/rumor), literally 'town talk and alley theories'. The exact historical origin is uncertain, but it follows a common pattern of pairing similar concepts for emphasis.