What is the term for a word that has the same meaning as another word?

The term for a word that has the same meaning as another word is 'synonym.' Synonyms are important in language because they provide alternatives for expression, allowing for more nuanced or varied communication. For example, the words "happy" and "joyful" are synonyms, as they convey the same or similar feelings.

In contrast, antonyms refer to words that have opposite meanings, which illustrates a different concept in vocabulary. Homonyms relate to words that sound alike but have different meanings, showcasing a different aspect of language and usage. Dialect refers to a particular form of a language that is specific to a region or social group, focusing on pronunciation, grammar, and vocabulary variations rather than meaning equivalence. Understanding synonyms enhances vocabulary skills and enriches writing and speaking abilities.