WordNet sense 1 (with no effort to conceal):

barefaced

WordNet sense 2 (open and observable; not secret or hidden):

open, overt

WordNet sense 3 (without the natural or usual covering):

denudate, denuded

WordNet sense 4 (lacking its natural or customary covering):

bare

WordNet sense 5 (lacking hair on all or most of the scalp):

bald-headed, bald-pated

WordNet sense 6 (having no hair or fur):

hairless