friendly fire

:  of, relating to, or befitting a friend: as

:  showing kindly interest and goodwill

:  not hostile

:  in a friendly manner :  amicably

:  one that is friendly

:  a native who is friendly to settlers or invaders

:  a match between sports teams and especially international teams that has no connection with league or championship play

:  the phenomenon of combustion manifested in light, flame, and heat

:  one of the four elements of the alchemists

:  burning passion :  ardor

:  to set on fire :  kindle

:  ignite

:  to give life or spirit to :  inspire