The actual meaning of that word may have nothing to do with why it was banned. The hashtag is blocked because it returns inappropriate or pornographic results that exceed a certain threshold. This is the reason why a lot of quiet innocent tags appear in the black list. Here are some of the innocent tags to be aware of:
#bra #IG #ilovemyinstagram #instagirl #instagram #iphone #iphone4s #iphoneography #lingerie #nude #panties #petite #photography #popular #popularpage #sexy #thinspiration #underwear #undies #like #bootie or #booties #instagood
This list is constantly changing, some tags are recovered and others are added, so be sure to double-check the tags you use.