noun which may take the genitive case particle 'no'
under the influence of; influenced by
Used as a noun followed by の to modify another noun, indicating that something is under the influence or effect of something else. Often appears in formal or written contexts.
彼はアルコールの影響下で事故を起こした。
He caused an accident while under the influence of alcohol.
その政策は強い政治的影響下にある。
The policy is under strong political influence.