空そら頼だのみ

noun, noun or participle which takes 'suru', transitive verb

vain hope; false hope; unfounded expectation

Refers to a hope or expectation that is unrealistic or without solid basis. Often used in the phrase 空頼みをする.

• 彼かれの助たすけを空そら頼だのみしても無む駄だだ。

  It's useless to pin vain hopes on his help.

• そんな空そら頼だのみはやめたほうがいい。

  You'd better give up such false hopes.