A last-ditch action is done only because there are no other ways left to achieve something or to prevent something happening. It is often done without much hope that it will succeed.
...a last-ditch attempt to prevent civil war.
ADJ : ADJ n
LAST-DITCH
Meaning of LAST-DITCH in English
Collins COBUILD Advanced Learner's English Dictionary. Английский словарь Коллинз COBUILD для изучающих язык на продвинутом уровне. 2006