Definition : The tendency of certain linguistic items to occur in specific syntactic contexts and not in others.
Example : Much and many + noun phrase tend not to occur in object/complement position in affirmative sentences. Eg: *There are many trees in my garden/ *She has much money - with alternative expressions such as a lot of being preferred. They do however occur in the equivalent negative sentences (There aren't many trees in my garden / She doesn't have much money), or in affirmative sentences in subject position : Many people have argued that.... / Much fuss has been made about ...
Example : Intensifying adjectives such as mere, utter, sheer etc can only be used in attributive position - It was mere folly / It was sheer nonsense / It was utter stupidity - and not in predicative position - *The folly was mere /*the nonsense was sheer / * His stupidity was utter.
(An asterisk * indicates an unnatural sentence)
Hoey, M. Lexical Priming - A New Theory of Words and Language, Routledge