When you are in the movie theater and you cum on the back of someones head when they're not looking.
Wow, Pablo just gave me a "alabama Lincoln" while watching Cars 2, I didn't even have any napkins.
To ejaculate forcefully into the back of someone's head at a movie theater.
The term originates from Abraham Lincoln being assasinated and being shot in the back of a head in a theater.
I was so invested in Cars 3, I hadn't noticed Pablo gave me an Alabama Lincoln until the credits.