food chain 
noun
1A series of organisms each dependent on the next as a source of food.The press initially fingered Asian restaurants as a likely source of this pollution of our food chain....
- What makes you so confident that the silver iodide will stay out of the food chain and not affect the environment?
- A huge hit to the base of the food chain should ripple up through fish and seabirds.
1.1 informal A hierarchical system or structure within a particular sphere or group: a small paper toward the bottom of the journalistic food chain...
- Having arrived in Hollywood, he then lived in a friend's closet and spent the next decade at the bottom of the Hollywood food chain.
- Although uneducated in the social nuances of the international cocktail set, he picked it up fast and, being from lower down the food chain, was especially observant.
- The world is about to be shown what it's like to be at the bottom of the food chain.
2The series of processes by which food is grown or produced, sold, and eventually consumed: they have taken all reasonable steps to ensure that no contaminated products enter the food chain...
- But the emerging structure of the food chain is taking more and more of the decision making out of the hands of farm entrepreneurs.
- Pembrokeshire dairy farmers are making big efficiency gains and those savings must not be snatched away further up the food chain.
- These standardizations, driven by the interests of a few retailers, are turning the food chain into a managed system - managed by the concentrated market clout of retailers.