An Utterance is any stretch of talking by one person, before and after which
there is a silence on the part of the person. It is used by a particular speaker on a
particular occasion of a piece of languages, such as a sequence of sentences, or a
single phrase, or even a single word.
Blackmore, D. (1992), Understanding Utterances. An Introduction to
Pragmatics, Blackwell Publishers.

A Conversation is a form of interactive, spontaneous communication between two or more people who are following rules of etiquette. It is a social skill that is not difficult for most individuals. Conversations are the ideal form of communication in some respects since they allow people with different views on a topic to learn from each other.
http://en.wikipedia.org/wiki/Conversation
To have a conversation, two or more people must co-operate, think about others’ feelings and experiences, and give each other room to talk. Moreover, a conversation is a reciprocal process and a very sophisticated activity that involves
people agreeing about the topic and immediate response.
http://www.infed.org/foundations/f-conv.htm

Implicature is used to account for what a speaker can imply, suggest or mean
as distinct from what the speaker literally says. The term “implicature” is used by
Grice (1975) to account for what a speaker can imply, suggest, or mean, as distinct
from what the speaker literally says. The word “implicature” is derived from the verb “to imply”, as is its cognate “implication”. “To imply” means “to fold” something into something else (from the Latin verb plicate “to fold”); hence, that which is implied, is “folded” and has to be “unfolded” in order to be understood.
Levinson, S. C. (1983), Pragmatics, Cambridge University Press.

Maxim is a brief statement that contains a little piece of wisdom or a general
rule of behavior. Maxims are sometimes written by a single author, for example in
the form of philosophical quotations. When a maxim has no specific author, it
becomes a kind of proverb – something that just emerges from the culture and
survives because people use it, not because any specific person wrote it in a book.
The defining characteristic of a maxim is that it’s pithy – that is, it packs a lot of
meaning into just a few words.
Example 1: Rome wasn’t built in a day.
This famous saying is a good example of a maxim with a metaphor in it.
Rome is a metaphor for whatever you might be working on – a career, a
relationship, a long-term project, etc. Whatever it is, the idea of “building Rome”
reminds you that these things take time.
https://literaryterms.net/maxim/

Maxim Violations
According to Grice (1975), a violation occurs when speakers intentionally try
to apply certain maxims in their conversation in order to cause misunderstanding
among their participants or to achieve other goals. In the preceding exchange, the
student's response has nothing to do with the teacher's question. One reason for this
response could be that the student is attempting to avoid the teacher's interrogation

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