Moonlight was the light of the moon.
The only known way to kill a Haemovariform was over-exposure to the moonlight on which they thrived. (TV: Tooth and Claw)
The Luftwaffe was guided by moonlight on nights when this proved possible while attacking British cities during the Blitz. (PROSE: The Time Travellers)
Behind the scenes
Moons don't actually emit light; moonlight is often the reflection of light over the moon's surface from a nearby star.