Meaning Allah is perfect in an absolute sense without any defects or imperfections of any kind. Usually translated as Glory be to Allah.
The meaning of SubhanAllah is making Allah pure, and it is bound to its original word (sabh, meaning void) as if ones said, I verily absolve Allah from all evil.
The origin for the word is sabh, voidness, or tasbeeh, making something void.
This would render the term SubhanAllah to mean Allah is void. However the word means more than that. SubhanAllah means ‘Allah is void of all evil’, where ‘of all evil’ is left unsaid but always understood by the believers.
And this is the way SubhanAllah is used in the Quran. For example it says; “SubhanAllah amma yasifun – Void is Allah from that (evil) which they ascribe (to Him).” (37:180)