Final answer:
The ability to create new words or give new meanings to existing ones, such as 'hardware' evolving to 'spyware', demonstrates generativity in language, which is a unique feature that allows for endless creativity in our communication.
Step-by-step explanation:
The process by which new words are formed from existing ones, or existing words take on new meanings as described in the question, is an example of generativity in language. This aspect of language refers to our ability to use a finite set of words and grammatical structures to produce an infinite number of sentences and new expressions. This characteristic allows us to talk about new concepts, whether they are concrete or abstract, and to adapt our language to new technologies and social phenomena.
Examples of this generativity are the formation of new words like 'spyware' from 'hardware', and the adaptation of nouns such as 'e-mail' and verbs like 'texting' to fit new technological advances.