Who is Kadachana ? - Is it Arjun? in Mahabharat?

Kadachana is not a name. it is not Arjuna's name. please read this.

Bhaktivedanta VedaBase: Bhagavad-gītā As It Is 2.47

karmaṇy evādhikāras te

mā phaleṣu kadācana

mā karma-phala-hetur bhūr

mā te sańgo 'stv akarmaṇi

SYNONYMS

karmaṇi — in prescribed duties; eva — certainly; adhikāraḥ — right; te — of you; mā — never; phaleṣu — in the fruits; kadācana — at any time; mā — never; karma-phala — in the result of the work; hetuḥ — cause; bhūḥ — become; mā — never; te — of you; sańgaḥ — attachment; astu — there should be; akarmaṇi — in not doing prescribed duties.

TRANSLATION

You have a right to perform your prescribed duty, but you are not entitled to the fruits of action. Never consider yourself the cause of the results of your activities, and never be attached to not doing your duty.

Hence, Bhagavadgeetha, the Hindus' religious text has a very famous saying which in Sanskrit begins as "Karmanye vadhikarasthe ma phaleshu kadachana" meaning "Perform your duty but donot anticipate results"

I have never heard the name kadachana... Im assuming this is hindu related, and I didnt even know that arjun had any other names....

But there are few here who know much about the vedas, and i am no exception... So i would be surprised if you got a real answer here...

"KarmanyeVadhikaraste MaPhaleshu KadachaNa"

This means, Doing the Karma or actions is our right, but never to expect the fruits of action.

The fruits of labor come to us as the Supreme wills.

Here "Kadachana" is not Arjun, but should be read as Kada--Cha--Na, meaning never ever.

thanks

:)

Kadachana in the Shlok quoted by you tentatively means NEVER