To "kill" a yarn, means to break it's fibers, "locking" them in place with a hot clothes iron. (more or less). There really aren't too many times when you actually would want to "kill" a crochet project. Usually, when blocking, you hold a hot steam iron OVER the item WITHOUT touching it. If you were to touch it with the iron, you might "kill" it.
So, I'm blocking a swatch of SWTC's Amaizing 100% Corn Fiber. Now, I don't know what to do to block corn fiber, so I figure, I'll try it! First, the yarn is really lovely. The HOVERING is going well, so I figure, It's corn, so is that closest to "cotton" on the iron or is it closer to "linen"?
I've swatched a "square-ish" shape, so I tap the iron down and one of the corners is still peeking out from the iron, I lift the iron and ITS STUCK!!!! AAAAHHHHH!!!!! I grab the available corner (and thank God that I didn't cover the whole motif, note to self, never cover the whole motif when experimenting...) Anyway, I killed it. It's dead. Fibers immediately ripped from the swatch and stuck onto the iron. Matter of fact, here's the iron. It's kind of like a "sneak peek" isn't it? Can you see the motif on the iron?
Now, look at these two photos. The first one shows the surface of the 'alive, un-killed' swatch and the second is the 'killed' swatch. Can you see the damage. Wow, I wonder if I can get this stuff off my iron, or I'll have to go out and get a new one. (ugh, anyone know how to get corn off an iron?)