1.Definition: (used of persons or their behavior) not acceptable or reasonable
2.Definition: not acceptable; not welcome
"A word unacceptable in polite society", "An unacceptable violation of personal freedom"
3.Definition: not adequate to give satisfaction
"The coach told his players that defeat was unacceptable"
4.Definition: not conforming to standard usage
"The following use of `access' was judged unacceptable by a panel of linguists; `You can access your cash at any of 300 automatic tellers'"