reserved
bashful
boggling
cautious
cowardly
coy
demure
demurring
deprecative
deprecatory
distrustful
doubtful
faltering
fearful
fearing
fearsome
goosy
hesitant
hesitating
in fear
jibbing
jumpy
lowly
modest
mousy
nervous
qualmish
rabbity
reluctant
retiring
scary
scrupling
scrupulous
self-deprecating
self-depreciating
self-depreciative
self-distrustful
self-doubting
self-effacing
shaky
shilly-shallying
shivery
shrinking
shy
skittery
skittish
squeamish
apologetic
brusque
conciliatory
derisive
disdainful
dismissive
halfhearted
heartfelt
incredulous
ingenuous
kindliest
offhand
perfunctory
regretful
rueful
sheepish
sidelong
supercilious
unknowing