Become limp is a term used to describe the physical state of something that has lost its stiffness or strength. SAG, WILT, DROOP, and FLAG are all words used to describe this state. SAG is a verb meaning to sink or settle from pressure or weight. WILT is a verb meaning to become limp or DROOP, usually from lack of water. DROOP is a verb meaning to hang down limply. FLAG is a verb meaning to become weak or feeble. All of these words can be used to describe the physical state of something that has become limp.