What does the term residual risk mean in the composite risk management process?

Answer 1

"The residual risk is the risk or danger of an action or an event, a method or a (technical) process that, although being abreast with science, still conceives these dangers, even if all theoretically possible safety measures would be applied (scientifically conceivable measures)"

Basically it means that it's the risk that remains once you've done everything you could in order to cancel out risk.

Answer 2

Residual Risk refers to those risks that are expected to remain even after implementing the risk responses.