Why is Eid known as "Akhtar" in Pashto?

[khushal]

I've never heard a Tajik/Farsiwan call Eid "Akhtar." Maybe Pashtunized Tajiks in Kandahar use it, but I don't think anyone would call it Akhtar while speaking Farsi.

All the Farsiwan(mostly kabuli and panjsheri) I know say Akhtar and I have some family members that have married farsiwan women and they all say that too but you could be right, maybe they are saying it because they are around pashtuns or to pashtuns and not with each other.

I was under the impression it was an Afghan(pashtun and farsiwan) thing.