The term INTENSIFY, WITH 'UP' can be broken down into three crossword solutions: AMP (3 letters), RAMP (4 letters), and REV (3 letters). AMP stands for Amplify, which means to make something louder or more powerful. RAMP stands for RAMP UP, which means to increase in intensity or magnitude. Finally, REV stands for REV UP, which means to increase the speed or intensity of something. All three of these terms refer to the idea of intensifying something, with the addition of the word 'UP' to each term.