"The window in the kitchen is very big."

Translation: اَلْشُّبّاك في ٱلْمَطْبَخ كَبير جِدّاً.

[Karim653362]

Both ways work in regular use of arabic

[Sara.Fasl]

shouldn't we use feminine form of the adjective for irregular plural form?
الشباك الکبیرة

[Haneen767742]

It is not plural form it is only one شباك
The plural form for it it's shababiek شبابيك
هذا الشباك الكبير
هذه الشابيك الكبيرة

[Sara.Fasl]

You are absolutely right :)