noun, noun or participle which takes 'suru', transitive verb
Literal sense: a layer attached to the back of something for reinforcement or finish, such as fabric lining or paper backing.
このスーツは裏打ちがしっかりしている。
This suit has a sturdy lining.
ポスターに裏打ちをして補強
I reinforced the poster by adding a backing.
noun, noun or participle which takes 'suru', transitive verb
support; backing up; bolstering
Figurative sense: providing evidence, authority, or resources that strengthen an argument, theory, or position.
彼の主張はデータの裏打ちがある。
His claim is backed up by data.
理論を裏打ちする証拠が必要だ。
We need evidence to support the theory.