A white tablet devised by Bayer Industries to finally solve the world's pigeon problems. Also known as "pigeon killer".
I gave alka-seltzer to a pigeon and it exploded.
You-drop alka-seltzer into cup
Woman- what the fuck did you just roofie me?
You-Pull out alka-seltzer and explain its just that
she might then say something along the lines of "Oh my Gosh that is so funny we should have sex
When you drop your balls into somebody's carbonated beverage. When dropped in, they make the sound "plop plop. fizz fizz", much like the advertisement for the original product.
Dude, go over there and alka-seltzer that guy's drink.
The act of taking a duece while in a hot tub. Since the hot tub is already churning water, bubbles, and blowing hot water, the turd will quickly dissolve like an alka-seltzer, leaving a nice fecal coloring to the water.
I was in Laura's hot tub last night, listening to Aaron Neville, and sippin' on a chilled glass of white zinfandale, when I decided to leave an alka-seltzer.