The linguist H.P. Grice observed that people don't just communicate what they say. They communicate what they imply, what they leave out, and what they expect the listener to infer. This gap between what is said and what is meant is subtext.
In conversation, subtext appears in: the question behind the question, the reassurance-seeking disguised as casual chat, the anger expressed as a joke, the distance expressed as busyness, the love expressed as logistics.
Strategic vagueness
Deliberately ambiguous messages that give the sender deniability while still communicating the underlying feeling.
The real question
"Are you busy tonight?" often means something else entirely. We read for the ask beneath the ask.
Encrypted emotion
Care expressed as sarcasm. Concern expressed as instruction. Affection expressed as teasing. The emotion is real; the encoding is indirect.
What wasn't sent
Long gaps, deleted topics, subjects that were circled but never named. Absence is a form of communication.