(a.) Tending to conceal, or to keep private; as, a secretive disposition\.

close closemouthed dark discreet disinclined to communicate evasive excretory lachrymal lachrymose lacrimatory lactational lacteal lacteous meaningless mum reserved reticent rheumy salivant salivary salivous secret secretional secretory seminal serous shifty sialagogic silent spermatic taciturn tight-lipped uncommunicative unconversable unsociable watering watery