Letters that make speedup
s, d, e, p, u are letters that make 'speedup'
speedups is a word created by adding a letter to 'speedup'
1 possible definitions for 'speedup'
Under this definition, speedup is a noun and has the following properties:
acceleration, quickening have the same meaning as 'speedup'
deceleration has the opposite meaning of speedup
accelerate, speed up, quicken, speed are derivatives of 'speedup'.