The term 'sprung up' can be described by four different crossword solutions: risen (5 letters), arisen (6 letters), AROSE (5 letters), and grew (4 letters). Risen and arisen both mean to move from a lower to a higher position, while AROSE means to come into existence or to begin to happen. Grew is used to describe an increase in size, number, intensity, or amount. All of these words are related to the idea of something coming into being or increasing in some way.