Body language

Body language is "a type of nonverbal communication in which physical behaviors, as opposed to words, are used to express or convey information": posture, gesture, facial expression, eye movement, touch, the use of space. In fiction, Carla Hoch's Writer's Digest definition applies it to the page: "any nonverbal communication that characterizes someone in a scene"; without it "a scene with no body language is like a face with no expression."

On the page it is the physical layer of subtext: what the body says while the dialogue says something else, the action-beat alternative to the dialogue tag, a beat of business carrying feeling beside the speech. Hoch's rules: "The body language of each character in a scene should be as unique as their dialogue," and "you need to show a cluster of behaviors," one cue alone being ambiguous, the caution Wikipedia raises about single signals. The two channels are balanced in how to write dialogue.