1) Acceleratory 2) Increasing 3) Increasing the velocity of 4) Tending to accelerate 5) Tending to increase velocity 
• (a.) Relating to acceleration; adding to velocity; quickening.
Ac·cel'er·a·tive adjective Relating to acceleration; adding to velocity; quickening. Reid. 
[adj] - tending to increase velocity
accelerative Tending to increase velocity or speed.
acceleratory adjective tending to increase velocity
tending to accelerate; increasing the velocity of.