Half the globe (three-quarters of them) is quietly present (10)
I believe the answer is:
hemisphere
'half the globe' is the definition.
(I've seen this before)
'three-quarters of them is quietly present' is the wordplay.
'three quarters of' becomes 'h' (I can't justify this - if you can you should give a lot more credence to this answer).
'them' becomes 'em' (abbreviation).
'quietly' becomes 'p' (p for piano and quiet).
'present' becomes 'here' (both can mean in attendance).
'h'+'em'+'is'+'p'+'here'='HEMISPHERE'
Can you help me to learn more?
(Other definitions for hemisphere that I've seen before include "part of the world" , "Cerebral division" , "Half of the earth" , "See 6" , "covers half the world" .)