Chuck is bashful (3)
I believe the answer is:
shy
I believe this is a double definition.
'chuck' is the first definition.
(both can mean to throw)
'bashful' is the second definition.
(bashful means shy or reserved)
'is' acts as a link.
(Other definitions for shy that I've seen before include "guarded" , "Nervous or timid in company" , "cast" , "Quick throw" , "Bashful or timid" .)