definition of
light up

[1] #1 light up v. start to burn with a bright flame; "The coal in the BBQ grill finally lit up". wn

[2] #2 light up v. make lighter or brighter; "This lamp lightens the room a bit". wn

[3] #3 light up v. become clear; "The sky cleared after the storm". wn

[4] #4 light up v. ignite; "The sky lit up quickly above the raging volcano". wn

[5] #5 light up v. begin to smoke; "After the meal, some of the diners lit up". wn