What is Body Language?

Legal Definition
Body language is a type of non-verbal communication in which physical behavior, as opposed to words, is used to express or convey information. Such behavior includes facial expressions, body posture, gestures, eye movement, touch and the use of space. Body language exists in both animals and humans, but this article focuses on interpretations of human body language. It is also known as kinesics.

Body language must not be confused with sign language, as sign languages are full languages like spoken languages and have their own complex grammar systems, as well as being able to exhibit the fundamental properties that exist in all languages. Body language, on the other hand, does not have a grammar and must be interpreted broadly, instead of having an absolute meaning corresponding with a certain movement, so it is not a language like sign language, and is simply termed as a "language" due to popular culture.

In a community, there are agreed-upon interpretations of particular behavior. Interpretations may vary from country to country, or culture to culture. On this note, there is controversy on whether body language is universal. Body language, a subset of nonverbal communication, complements verbal communication in social interaction. In fact some researchers conclude that nonverbal communication accounts for the majority of information transmitted during interpersonal interactions. It helps to establish the relationship between two people and regulates interaction, but can be ambiguous. Hence, it is crucial to accurately read body language to avoid misunderstanding in social interactions.
-- Wikipedia
Legal Definition
Nonverbal communications sent by a person to another person. AKA kinesic communications. Refer to nonverbal communication.