The term 'Cause for Quaking' can be summed up by the crossword solution of 'FEAR'. FEAR is an emotion that is experienced when a person is faced with danger or a perceived threat. It is a natural response to a situation that is perceived as dangerous and can cause physical reactions such as increased heart rate, sweating, and trembling. FEAR can also lead to avoidance behavior, which can prevent people from taking risks or engaging in activities that could potentially be beneficial.