I'm writing this question from my office so kindly allow my rough style.
Becuase I am a guid tour, I am checking the site in English where I will bring the non-native ( to my country ) visitors.
I will bring them here.
It says
he ceiling of the inner chamber is coffered and decorated with paintings of over a hundred flower varieties found around Nikko.
I am very sorry I am unable to copy the explanation by Merriam Unabridged, because I don't understand at all.
Could the verb "coffer" here, simply be almost the synonym of "to decorate"?
Thank you for your kind assistance in advance.(m_m)