To add money to a cellular phone.
The next time I'm due to top up is April 6th.
by GuidoPosse69 February 21, 2005
Returning to a state of filledness from a previously empty or not qutie full state.
Sup wid dat mophone be'in all empty n dat! Am chip'in down da atm n get mo topup ja nata meen... init
by Dylanmi September 01, 2008
On a certain unnamed Caribbean island (not Jamaica) top up means one who smokes ganja.
Dat white boy ok,how you know him,he top up?
by BSquared June 19, 2007