adjective

not openly acknowledged or displayed.

covert operations against the dictatorship

secret,furtive,clandestine,surreptitious,stealthy,cloak-and-dagger,hole-and-corner,hole-in-the-corner,closet,behind-the-scenes,backstairs,back-alley,under-the-table,hugger-mugger,concealed,hidden,private,sly,sneaky,underhand,undercover,underground,black,hush-hush

noun

a thicket in which game can hide.