Ray L. Birdwhistell (September 29, 1918 – October 19, 1994) was an American anthropologist who founded kinesics as a field of inquiry and research. Birdwhistell coined the term kinesics, meaning "facial expression, gestures, posture and gait, and visible arm and body movements". He estimated that "no more than 30 to 35 percent of the social meaning of a conversation or an interaction is carried by the words." Stated more broadly, he argued that "words are not the only containers of social knowledge." He proposed other technical terms, including kineme, and many others less frequently used today. Birdwhistell had at least as much impact on the study of language and social interaction generally as just nonverbal communication because he was interested in the study of communication more broad