The term 'fall uncontrollably' can be summarized by the crossword solution 'PLUNGE, ' which is a six-letter word. To 'PLUNGE' means to move quickly and suddenly in a downward direction, often with a feeling of loss of control. This term is often used to describe a person or object falling from a great height or into a body of water. It can also be used to describe a sudden and dramatic decrease in something, such as a stock market crash.