What's the adjective for phaticity? Here's the word you're looking for.
phatic
(linguistics) Pertaining to words used to convey any kind of social relationship e.g polite mood, rather than meaning; for example, "How are you?" is often not a literal question but is said only as a greeting. (Similarly, a response such as "Fine" is often not an accurate answer, but merely an acknowledgement of the greeting.)
