From Longman Dictionary of Contemporary Englishlink in the chainlink in the chainDO something/TAKE ACTIONone of the stages involved in a process → link
Examples from the Corpus
link in the chain• I am a link in the chain, a bond of connection between persons.• Development itself can be a link in the chain of stress and violence.• That's what I was - a link in the chain.• The schools are a critical link in the chain, but only one.• The law does not allow the consumer to ignore the intermediate links in the chain.• He felt like a useless and unused link in the chain.• This time, it was the primacy of the office as gathering place that was the weak link in the chain.• This is the weakest link in the chain, and we have a system for chasing referees and eventually going elsewhere. 