A 5-letter antonym for "loiter" is "hasten." While "loiter" means to linger or remain in one place without purpose, "hasten" conveys the idea of moving quickly or acting with speed and intention.
hurry, leave
short
alive
found
awake
awake
Loiter.
Loiter Squad - 2012 Poetic Justice 2-5 was released on: USA: April 2013
plain, dingy, dusty
Plain
loll, laze, loiter
The opposite could be dawdle, delay, linger, plod, or tarry.