Synonym (noun)

1. A word or phrase that means exactly or nearly the same as another word or phrase in the same language.
2. A word or phrase having the same or nearly the same meaning as another in the language, e.g. happy, joyful, elated.

Origin:

Late 17th century: via latin from greek sunōnumon, from sun- "together" + onoma "name".

Examples:

1. The word 'big' is a synonym of 'large'.
2. The synonym of 'happy' is 'joyful'.
3. "Pretty" is a synonym for "attractive".
4. "Pleasant" is a synonym for "agreeable".
5. "Amusing" is a synonym for "entertaining".