Reticent (3)
'reticent' is the definition.
(both can mean withdrawn or timid)
This is the entire clue.
(Other definitions for shy that I've seen before include "'Lacking self-confidence, timid (3)'" , "Retiring; fling" , "Reserved" , "Chary" , "Embarrassed in company" .)
'reticent' is the definition.
(similar in meaning)
This is the entire clue.
(Other definitions for taciturn that I've seen before include "Tending to silence" , "Disinclined to speak" , "Far from talkative" , "withdrawn" , "Uncommunicative, of few words" .)
'reticent' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for reserved that I've seen before include "Unemotional; put by" , "not forthcoming" , "Booked - reticent" , "Kept back" , "Retiring" .)