Trunk initially dropped roughly (2,2)
I believe the answer is:
or so
'roughly' is the definition.
('10 or so' can mean 'roughly 10')
'trunk initially dropped' is the wordplay.
'trunk' becomes 'torso' (both can mean a person's chest).
'initially dropped' means to remove the first letter.
'torso' with its first letter taken away is 'OR SO'.
(Other definitions for or so that I've seen before include "Approximately" , "Something like" , "roughly" , "More or less" .)