Paralanguage

par-a-lan-guage (pr-lnggwj)

1. Nonverbal communication, like a snort, chuckle, guffaw, a hiss or a shush, and tone of voice.
Soon, he only heard paralanguage and similar forms of deeper communication, like the way that Kristi’s head bobbed, as she giggled and flirted with the lovers of her coworkers.*

Synonyms: attitude, body language, intonation, nonphonemic properties of speech, nonverbal communication.

* A quote from my upcoming novel. How's that for pretentious and self-referential?