Backformation.
A very specialized type of reduction process is known as
backformation. Typically, a word of one type (usually a
noun) is reduced to form a word of another type (usually a
verb). A good example of backformation is the process
whereby the noun television
first came into use and then the verb televise was created
from it. Other examples of
words created by this process are: donate (from “donation”),
emote (from “emotion”),
enthuse (from “enthusiasm”), liaise (from “liaison”) and
babysit (from “babysitter”).