instance(redirected from in the first instance)
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a. an expression derived from another by instantiation
b. See substitution
instance(1) A single copy of a running program. Multiple instances of a program mean that the program has been loaded into memory several times.
(2) In object technology, a member of a class; for example, "Lassie" is an instance of the class "dog." When an instance is created, the initial values of its instance variables are assigned.