What defines a homonym?

A homonym is defined as words that have the same spelling and pronunciation but possess different meanings. This definition captures the essence of what a homonym is, as it encompasses examples like "bat," meaning the flying mammal or the implement used in sports, both of which are pronounced and spelled the same way but convey completely different concepts.

Other options do not accurately reflect this definition. For instance, words with similar meanings refer to synonyms, which are distinct from homonyms. Words that rhyme may share similar sounds but do not necessarily have the same spelling or meaning. Lastly, words with opposite meanings are called antonyms, again distinguishing them from the concept of homonyms. Thus, understanding the unique characteristics of homonyms clarifies their definition and usage in language.