1cause 
/ˈkɑ:z/ noun
plural caus·es /ˈkɑ:z/ noun 1 [count] : something or someone that produces an effect, result, or condition : something or someone that makes something happen or exist
▪ His symptoms had no apparent physical causes. ▪ She is the cause of all their problems. ▪ He died of/from natural causes. [=he died because of old age or an illness] — often + of ▪ The doctor determined the cause of death. ▪ The exact cause of the accident/fire is not known. 2 : a reason for doing or feeling something [noncount] ▪ The medicine was prescribed without good cause. — often + for ▪ There is some cause for concern. [=some reason to be concerned/worried] [singular] ▪ Their marriage was a cause for celebration. — see also probable cause 3 [count] : something (such as an organization, belief, idea, or goal) that a group or people support or fight for
▪ I can support a cause that means something to me. ▪ I'm willing to donate money as long as it's for a good/worthy cause.
▪ His symptoms had no apparent physical causes. ▪ She is the cause of all their problems. ▪ He died of/from natural causes. [=he died because of old age or an illness] — often + of ▪ The doctor determined the cause of death. ▪ The exact cause of the accident/fire is not known.
▪ I can support a cause that means something to me. ▪ I'm willing to donate money as long as it's for a good/worthy cause.
lost cause
: a person or thing that is certain to fail
▪ She decided her acting career was a lost cause. ▪ I'm a lost cause when it comes to anything technical.
▪ She decided her acting career was a lost cause. ▪ I'm a lost cause when it comes to anything technical.
make/find common cause
formal : to join together with someone in order to achieve a shared goal
▪ He has made common cause with political rivals to defeat the proposed new law.
▪ He has made common cause with political rivals to defeat the proposed new law.
