What did the term "secession" refer to during the Civil War?

The term "secession" during the Civil War specifically referred to the withdrawal of Southern states from the Union. This action was taken by several Southern states following the election of Abraham Lincoln in 1860, as they feared that his presidency would threaten the institution of slavery and their rights as states. The secession led to the formation of the Confederate States of America, a direct response to what the secessionists perceived as Northern aggression and an infringement on their sovereignty. The concept of secession was central to the conflict that unfolded during the Civil War, highlighting the deep divisions in the nation over issues of state rights and slavery. The other choices do not accurately reflect the historical context of secession during this period.