Read the room is a twentieth century idiom. We will examine the meaning of the common idiom read the room where it came from, and some examples of its idiomatic usage in sentences.
Read the room means to observe a group of people and understand their collective mood, emotions, opinions, and tendencies. Read the room usually refers to a literal roomful of people, but it may mean a certain demographic or clientele. The expression read the room is found as early as the 1970s, but in this case, it was used by a thief to mean to observe where things are located in a room and the thief’s access to them. In the 1990s, the phrase read the room began to be used by marketing executives to mean to understand the motivations, feelings, and mood of a certain group of people.
It’s harder to pick up informal gossip, “read the room,” take in the hundreds of informational cues that used to pepper the workday. (Newsweek)
Pelosi gave McCarthy a day to read the room. (Time)
By the time the 2pm national cabinet meeting rolled around, Berejiklian had read the room and softened her stance. (Sydney Morning Herald)