undo

[1]	loosen , loose , open , unfasten , unhook , unlace , unzip , unsnap , unbutton , untie , unpin , unlock , unbolt
[2]	unwrap , unmake , uncover , open , untie , unbind
[3]	cancel , annul , rescind , nullify , void , declare null and void , reverse , invalidate
[4]	untie , loosen
[5]	unwrap