veiled /veɪld/ BrE AmE adjective
a veiled threat, warning, attack, reference etc is expressed so that its exact meaning is hidden or unclear:
His speech is being seen as a veiled attack on asylum-seekers.
‘I’m impressed,’ said Greg, with thinly veiled (=only slightly hidden) sarcasm.
Jasper remained silent and his eyes were veiled (=you could not guess what he was thinking) .