The crossword solution for the term 'Top of Some Food Chains' is 'Lioness', which is a seven-letter word. Lionesses are the top predators in their food chain, as they are the apex hunters and scavengers in their ecosystems. They are the dominant species in their environment, and they have no natural predators. Lionesses are also the primary hunters in their pride, and they are responsible for providing food for their cubs.