Lights Up 

A musical masterpiece written and performed by Harry Styles

"Harry's new song Lights Up is such a bop!"
"Stream Lights Up by Harry Styles"

Lights Up by stylesmedicine October 15, 2019

Lights Off Baby 

A baby, one of whom's parents is so ugly, which required conception to occur in a darkened room.

Good god, check out that woman at the swingset with her Lights Off Baby.

Lights Off Baby by tetrameth June 20, 2010

lights are on but nobody is home 

Used when describing a person who is not all there mentally, that is inept socially etc, or appears to be a bit thick. Struggles to fit into normal society, and subsequently rejected and described to people as a bit slow.
May also be used lightheartedly if someone is perhaps day-dreaming and not paying attention when asked a question. Similar to, but not quite the same"a few beers short of a six-pack", or "a few screws loose."

What if we asked Dudley if he knows?
What? You're kidding me right? Theres no way he'd know. In fact stay away from that bloke
Why's that?
You know, The lights are on but nobody is home.
Oh, ok thanks for the warning.

I can't remember, hang on a sec, i'll ask Harold.
Harold, whats the price of that Xbox again, you know the one you bought from E-bay?
Huh?
I said, how much was that X-box you got from E-bay the other day?
Oh? umm, ahh, hang on a sec
Sorry for the hold up Mavis, old harold here is in another world, the lights are on but nobody's at home, heheh.

lights are on but nobody is home by jamie_ledge July 19, 2006

lights out 

In sports, it means great performance.

"Maddux was lights out on the road, winning 8 of his last 9 decisions."

lights out by erotica69 September 18, 2005

Lights Out 

Sudden unexpected death

Did you hear about the dude that dropped dead while running a marathon? His heart fucking exploded and it was lights out right in the middle of the course! People had to run around the body for over 10 minutes until they tarped the corpse.

Lights Out by Wordmaster Adam December 23, 2016

Lights of Censoring 

A blinding light emited from exposed private areas, it is often used in anime to censor nude scenes.

After lifting her skirt, he was blinded by the Lights of Censoring.

The Lights of Censoring allows otherwise explicit shows to be aired.

Lights of Censoring by fufulord October 9, 2014

Lights Out 

When two balls are shot into the last remaining cup in a game of beer-pong, eliminating the chance of an opponent rebuttal

G1 "why didn't you take your rebuttal shots?"

G2 "Conner and Ipp just went lights out on us."

G1 " HaHa...you guys got fucked"

Lights Out by buckkkkk April 23, 2009