Verse meaning
This is the verse translation, not a definition of the individual word.
When you are given a greeting, respond with a better greeting or return the same[1]. Indeed, Allah is the Reckoner of all things.
Source
[1] ‘Imrān ibn al-Husayn (رضي الله عنه) said: “A man came to the Prophet (ﷺ) and said: “Assalāmu ‘alaykum (Peace be upon you)”. He was replied to and sat down. The Prophet (ﷺ) said: “Ten (rewards)”. Then another one came and said: “Assalāmu ‘alaykum wa raḥmatu Allah (Peace be upon you and Allah’s Mercy)”. He was replied to and sat down. The Prophet (ﷺ) said: “Twenty”. Then another one came and said: “Assalāmu ‘alaykum wa raḥmatu Allah wa barakātuhu (Peace be upon you and Allah’s Mercy and His Blessings)”. He was replied to and sat down. The Prophet (ﷺ) said: “Thirty”. [Abū Dāwūd: 5195, At-Tirmidhī: 2689, Ahmad: 19948]
Source: QuranEnc.com · English Translation - Rowwad Translation Center
Listen to the verse context