Final answer:
Inversion is a stylistic device where the key word or phrase is placed at the end of the sentence. It adds emphasis and surprise to the writing.
Step-by-step explanation:
The stylistic device known as using a key word or phrase at the end rather than the beginning of a sentence is called inversion. It is a technique employed to create emphasis or surprise in writing. In the given example, the statement "she's an inspiration, a best friend, and a teacher; she's also my mom" is inverted by placing the key word "mom" at the end of the sentence, creating a memorable and impactful effect.
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