SUMMARY
Language has an inventory of words and expressions (e.g. especially, sort of, loosely speaking) used to communicate that what is being said is not exactly precise or complete. Referred to as hedges, they provide support for the conception of prototypically organized categories, developed by Eleanor Rosch in the 1970s and elaborated by her followers in subsequent decades. Given the fact that hedges are extremely useful for lexicographers in defining, this paper examined the frequency and distribution of hedges in major English dictionaries over the past centuries. One of the findings of this research is the fact that, although hedges have been used in English lexicography since Johnson-1785, their use has intensified in certain dictionaries since the rise of prototype theory, suggesting that recent defining practice in these dictionaries must have been influenced by this theory. Other factors determining the use of hedges were explored.