A night without armor

The act of having sex without a condom, especially with the singer-songwriter Jewel.

Etymology: Jewel's 1998 poetry collection, A Night without Armor

Anthony Kiedis: How was the concert last night?

Flea: Sick. I hooked up with Jewel!

AK: Did you use a rubber?

Flea: Nah, dude, it was a night without armor.