The term 'Fell Back' can be described in four different ways: ebb (5 letters), retreat (9 letters), relapse (8 letters), and give ground (10 letters). Ebb means to gradually recede or fade away, while retreat means to withdraw from a position or situation. Relapse is a return to a previous condition or state, and give ground means to yield or surrender. All of these terms describe the action of falling back, which is the act of retreating or withdrawing from a position or situation.