What is an example of a morpheme?

A morpheme is the smallest unit of meaning in a language. It can be a whole word or a part of a word, such as a prefix or suffix. The prefix "un-" is an excellent example of a morpheme because it modifies the meaning of the base word it attaches to, often indicating negation. For instance, when "un-" is added to the adjective "happy," it creates the word "unhappy," which conveys the opposite meaning.

In contrast, a single letter like "p" does not convey meaning on its own, and while the word "cat" is a complete and meaningful unit, it is a whole word rather than a morpheme. Finally, the phrase "at home" contains multiple words that together convey a meaning, but it does not represent the smallest unit of meaning, as each word within the phrase is made up of individual morphemes. This makes the choice of "un-" the best illustration of a morpheme.