Homonym: er (Suffix)
The suffix "er" is commonly used in the English language to indicate a person or thing that performs a specific action. For example, in the word teacher, the suffix shows that the person teaches. Similarly, in runner, it indicates someone who runs.
Additionally, "er" can also denote a comparative form of adjectives, such as in taller or smarter. This usage helps to compare two entities, showing that one has more of a quality than the other. Overall, "er" serves important grammatical functions in English.