span·ner 
/ˈspænɚ/ noun
plural span·ners /ˈspænɚ/ noun put/throw a spanner in the works
informal : to cause something to not go as planned
▪ We were ready to start the project when the bank threw a spanner in the works by denying the loan.
▪ We were ready to start the project when the bank threw a spanner in the works by denying the loan.
