lacking beauty or charm; "as unattractive as most mining regions"[ant: attractive ]

lacking power to arouse interest; "being unemployed is a most unattractive prospect"

not appealing to the senses; "untempting food"

adjective

bad-looking , beastly , deformed , disfigured , disgusting , frightful , gross , grotesque , hideous , homely , horrid , monstrous , not much to look at , plain , repelling , repugnant , repulsive , revolting , unalluring , unappealing , unsightly , uncomely , unlovely , frumpish , rude , ugly , unappetizing , undesirable , uninviting