An ELT Glossary : Negotiation of Meaning

Negotiation of meaning can occur in any type of discourse, but is typically of primarily transactional discourse  - ie interaction where the content of the message is predominant rather than the social relationship between the participants. For example, imagine a conversation in a greengrocer's shop :

Customer : I'd like 2lbs of those apples please.
Greengrocer : These Cox's or the Granny Smith's?
Customer : The Cox's please.
Greengrocer : OK - did you say 2lbs?
Customer : Yes, that's right.

In this situation the greengrocer recognises (in the first instance) or suspects (in the second) that he hasn't fully understood the customer's meaning and queries or checks it - it's obviously important to the transaction that he understands exactly what she wants and he therefore "negotiates meaning"  until he understands fully. 

Another example of negotiating meaning is when the speaker makes a mistake and the listener realises there is something that s/he doesn't understand. This may lead to a situation of other repair or, particularly if the speaker is a language learner of initial misunderstanding and clarification.

A : I bought this book at the library today.
B:  You bought it at the library. What - are they selling some of their books?
A: No... the library - Waterstones in  Blackheath Road.
B: Oh, you mean the bookshop.
A: Yes, yes, sorry, the bookshop.

Swain, in her Output Hypothesis, suggests that this need to negotiate meaning because language has been used incorrectly and the speaker has been misunderstood is a major influence on language acquisition. Recognising that they have not made themselves clear "alerts" the speaker to the existence of a problem in their language output. When this problem is resolved, they are therefor more likely to "notice" and therefore acquire the correct form.