Amessage expressed through nonlinguistic means is called

nonverbal communication

Explanation:

When communication is done through methods that do not use language it is known as nonverbal communication. Gestures, distance, touch, facial expressions, time, modulation of voice and eye contact are used in nonverbal communication.

Most animals communicate nonverbally instinctually without conscious thought. Almost 60-70 percent of communication takes place nonverbally.

Hence, the statement here is referring to nonverbal communication.