look up any word, like the eiffel tower:
 
1.
1. A soothing song with which to lull a child to sleep.

2. A kick-ass book about how these songs can kill, written by a guy named Chuck Palahniuk who also wrote the novel Fight Club.
Yes, it is highly unknown that a lullaby can not only make a child sleep, but kill them, too.
by Athena Kay February 21, 2004
 
2.
A song usually made for the females in which the singer talks about love and catching feelings for females. Usually a hardcore rapper sells out by making one of these.
That rapper Sold out, he made a "Lullaby ".
by Bad Boy AKA Baby Boy January 09, 2009
 
3.
Book that beats the shit out of Death Note. Story of a man who finds out that a lullaby he sung to his late son kills, and he and a friend try to keep it out of the hands of a psycho.
Lullaby beats the crap of Death Note... fuckin' weeaboos.
by OLOL September 05, 2007