“Frailty, thy name is woman”. Hamlet said this when his mother remarried suddenly and though Hamlet meant that his mother was not strong enough to resist marriage, Shakespeare could as well have written, “Frailty, thy name is human”. As Michael Crichton says, “And I think the answer is that we are, in reality, terribly frail animals. And we don't like to be reminded of how frail we are—how delicate the balances are inside our own bodies, how short our stay on Earth, and how easily it is ended.”
Frailty in medicine has a specific definition, characterized by a decline in functioning across multiple physiological systems, accompanied by an increased vulnerability to stressors .
It is an evolving concept and hence there are many different definitions and classification systems in play. One of the more commonly used systems defines frailty when one or more of these five conditions is present