ban 

[ban] 

verb 

banned (past tense) · banned (past participle) 

officially or legally prohibit: 

"he was banned from driving for a year"; "a proposal to ban all trade in ivory" 

officially exclude (someone) from a place: 

"he once was banned from a casino in Reno." 

Origin 

Old English bannan ‘summon by a public proclamation’, of Germanic origin, reinforced by Old Norse banna ‘curse, prohibit’; the noun is partly from Old French ban ‘proclamation, summons, banishment’. 

Book bans refer to books that have actually been removed from a bookstore or library due to complaints from patrons or customers. 

challenge

verb 

verb: challenge; 3rd person present: challenges; past tense: challenged; past participle: challenged; gerund or present participle: challenging

1. invite (someone) to engage in a contest
   1. "he challenged one of my men to a duel"

• enter into competition with or opposition against.
  • "the beauty industry as we know it is being challenged by a group of pioneers hoping to change the way we see our bodies"
• make a rival claim to or threaten someone's hold on (a position).
  • "they were challenging his leadership"
• invite (someone) to do or say something that one thinks will be difficult or impossible.
  • "I challenge the Minister to deny these accusations"
• make demands on; prove testing to.
  • "a new way of life that would challenge them"

2. dispute the truth or validity of.

"it is possible to challenge the report's assumptions"

• Law
  • object to (a jury member).
  • (of a guard) order (someone) to prove their identity.
    • "the watchman did not challenge him"

3. Medicine

• administer an immunogenic or infectious agent to an animal or person, in order to study the resulting immune response or measure the efficacy of a vaccine.
• "the mice were challenged with the influenza virus"

A book challenge is when a patron makes a formal complaint about a material, asking for its removal from the library. Books are often challenged by patrons, but not officially removed or banned from libraries.

Censorship

noun

1. the suppression or prohibition of any parts of books, films, news, etc. that are considered obscene, politically unacceptable, or a threat to security.
"the regulation imposes censorship on all media"
2. (in ancient Rome) the office or position of censor.
"he celebrated a triumph together with his father and they held the censorship jointly"

Censorship aims to silence or remove any information, experience, or narrative that the censoring party deems offensive or objectionable.