Modifier

The word “modifier” refers to something that changes or affects the properties of something else, usually by altering it in some way without replacing it entirely.

### General Definition: - Modifier (noun): A person or thing that modifies or changes something.

Biology/Genetics:

1. A modifier gene is a gene that alters the expression of another gene.
2. An epigenetic modifier is a molecule or mechanism that modifies gene activity without changing the DNA sequence.