Communication of additional meaning, nuance, or emotion in speech
Paralanguage, also known as vocalics, is a component of meta-communication that may modify meaning, give nuanced meaning, or convey emotion, by using suprasegmental techniques such as prosody, pitch, volume, intonation, etc. It is sometimes defined as relating to nonphonemic properties only. Paralanguage may be expressed consciously or unconsciously. The study of paralanguage is known as paralinguistics and was invented by George L. Trager in the 1950s, while he was working at the Foreign Service Institute of the U.S. Department of State.
https://en.wikipedia.org/wiki/Paralanguage