not willing to be with other people

nonparticipating; avoiding company

shy (the usual word)

shy

(especially of a woman) pretending to be shy, modest

very modest

(especially of a woman) quiet and serious

reserved, affected

not having, not showing, much belief in one's own abilities

hesitant; unconfident

showing that one is inferior, less able etc

meek, unassuming

not striking or obvious

hidden, unnoticeable

not causing offence

not obnoxious; harmless

humble; modest

inferior, plain

having, showing, a low but honest opinion of one's own merits, abilities etc; not large in size or amount

shy

(of a person, character) slow to express feelings or opinions; (of a seat in a train, room in a hotel etc) kept for a person's later use

silent, unsociable; constrained

awkwardly self-conscious; (feeling) foolish or embarrassed because of having done something wrong

shy, embarrassed

(of a person) self-conscious and uncomfortable in the presence of others; (of animals etc) easily frightened

quiet and self-conscious

easily frightened

shy

not drawing attention to oneself; modest

shy

not communicative

shy, silent

not easily seen or noticed

inconspicuous

not too obvious or easily noticeable

keeping a low profile

not willing to be with others

unfriendly

(of a person) unusually quiet and shy

unsociable