unacceptable

not adequate to give satisfaction

• “the coach told his players that defeat was unacceptable”

not acceptable; not welcome

• “a word unacceptable in polite society”
• “an unacceptable violation of personal freedom”

used of persons or their behavior

• “impossible behavior”
• “insufferable insolence”

not conforming to standard usage

• “the following use of”
• “was judged unacceptable by a panel of linguists;”
• “'”