Just like graphite, which is used as a “dry” lubricant.

Just because it isn’t a very good lubricant, doesn’t mean it isn’t one. Hell, in some applications, water can be used as a lubricant. Are there better lubricants? Yes. Are there better penetrating oils? Yes (looking at you PB Blaster and Kroil). That also doesn’t mean WD-40 isn’t a penetrating oil.

The one with a "n" is, apparently, an accepted variant: http://www.merriam-webster.com/dictionary/res…

Way to reward brand loyalty, Apple.