incommunicative
uncommunicative
close
closemouthed
covert
dark
discreet
disinclined to communicate
evasive
excretory
furtive
lachrymal
lachrymose
lacrimatory
lactational
lacteal
lacteous
meaningless
mum
private
reserved
reticent
rheumy
salivant
salivary
salivous
secret
secretional
secretory
seminal
serous
shifty
sialagogic
silent
sly
spermatic
taciturn
tight-lipped
unconversable
unsociable
watering
watery
arrogant
devious
hesitant
inquisitive
moody
paranoid
reclusive
shy
sidelong
sneaky
suspicious
unfriendly
unpredictable
unsettle
wary