discreet

marked by prudence or modesty and wise self-restraint; "his trusted discreet aide"; "a discreet, finely wrought gold necklace"

unobtrusively perceptive and sympathetic; "a discerning editor"; "a discreet silence"

heedful of potential consequences; "circumspect actions"; "physicians are now more circumspect about recommending its use"; "a discreet investor"