Neither did I, but I suspect in the opposite direction to you. Honestly, I have used this term, with friends for years. I just checked with a couple on faceboo

Neither did I, but I suspect in the opposite direction to you. Honestly, I have used this term, with friends for years. I just checked with a couple on facebook, and we all visualised in terms of something like (if we imagine the real-world situation it references) putting a pillow over an ill/unconscious person's face to smoother them. Now, I'm not saying other people can't have a different interpretation, or there isn't a common one, but me and my friends have certainly held a different one for many years.