What does the term "synonym" mean?

The term "synonym" refers to a word that has the same or nearly the same meaning as another word. This definition highlights the concept of words being interchangeable in certain contexts, which is useful for expanding vocabulary and improving language skills. For instance, "happy" and "joyful" are synonyms because they convey a similar emotional state, allowing for variety in expression without changing the essential meaning. Understanding synonyms can enhance both written and spoken communication by enabling more nuanced and flexible language use.

The other options describe different linguistic phenomena. An antonym, for example, is a word with an opposite meaning, which is not applicable here. Slang refers to informal language that can vary by context but does not pertain to synonymy. Lastly, the origination of words from other languages relates to etymology, rather than to the concept of synonyms.