synonym synonym /ˈsɪnəˌnɪm/

noun

1. () Two words that can be interchanged in a context are said to be synonymous relative to that context  ( equivalent word , synonym )
   two words that can be interchanged in a context are said to be synonymous relative to that context
    "Happy" and "joyful" are often used as synonyms in many contexts.
   "Happy" and "joyful" are often used as synonyms in many contexts.