2
general::
bashful
shy and not willing to say very much
self-conscious
worried and embarrassed about what you look like or what other people think of you
timid
not brave or confident
reserved
not liking to express your emotions or talk about your problems
introverted
thinking a lot about your own interests, problems etc, and not liking to be with other people
withdrawn
quiet and not wanting to talk to other people, especially because you are unhappy
antisocial
not liking to meet people and talk to them
retiring
formal not wanting to be with other people
Longman-Thesaurus