Magnifier (noun)

1. A device, such as a lens or mirror, that makes things look bigger or clearer.
2. A device or tool used to magnify something.

Origin:

From middle english magnifien, from latin magnificare, from magnus "great" + -ficare "to make".

Examples:

1. He used a magnifier to read the small print.
2. She used a magnifier to inspect the jewelry.
3. The microscope has a built-in magnifier to enhance the image.
4. The magnifier is a useful tool for people with visual impairments.
5. A magnifier app is available on smartphones to magnify small text.