This is the 186th most frequent Tamil word.
நலன
The Tamil word "நலன" means "well-being" or "welfare" in English.
Here, 'நலனுடைய' (which means 'those who have welfare') depicts the students' moral or collective well-being or virtue.
நலனுடைய மாணவர்களுக்கு ஆசிரியர்கள் காதலோடு உதவும்.
Teachers lovingly assist students who have welfare in mind.
In this context, 'நலனுக்காக' (meaning 'for the welfare') is describing the purpose or motivation for which someone worked.
நலனுக்காகவே அவர் அதிகமாக உழைத்தார்.
He worked hard for the welfare.
Here, 'நலனை' (meaning 'the welfare') is used to denote overall well-being or benefits in general.