WordNet sense 1 (having its true character concealed with the intent of misleading):

masked, disguised

WordNet sense 2 (secret or hidden; not openly practiced or engaged in or shown or avowed):

covert

WordNet sense 3 (covered with or as if with clothes or a wrap or cloak):

clothed, draped, mantled, wrapped

WordNet sense 4 (overlaid or spread or topped with or enclosed within something; sometimes used as a combining form):

covered