Toss cape through timidity (7)
I believe the answer is:
shyness
'timidity' is the definition.
(shyness is a kind of timidity)
'toss cape' is the wordplay.
'toss' becomes 'shy'.
'cape' becomes 'ness' ('ness' can be a synonym of 'cape').
'shy'+'ness'='SHYNESS'
'through' is the link.
(Other definitions for shyness that I've seen before include "Timid behaviour" , "Timidity in company" , "Nervousness, timidity" , "Retiring quality" , "lack of confidence" .)