A change in the function of a word, as for example when a noun comes to be used as a
verb (without any reduction), is generally known as conversion. Other labels for this
very common process are “category change” and “functional shift.” A number of nouns
such as bottle, butter, chair and vacation have come to be used, through conversion, as
verbs: We bottled the home-brew last night; Have you buttered the toast?; Someone has
to chair the meeting; They’re vacationing in Florida. These conversions are readily
accepted, but some examples, such as the noun impact being used as a verb, seem to
impact some people’s sensibilities rather negatively.