OK, WikiIsNotaDictionary, but there seem to be a few math definitions around. The '''Cross''''''Product''' of two vectors is a vector perpendicular to both which has a length equal to the area of the parallelogram defined by them, and points in a direction such that it obeys the right-hand rule. That makes the '''Cross''''''Product''' anti-commutative. * ''a'' '''x''' ''b'' = -''b'' '''x''' ''a'' * ''(ka)'' '''x''' ''b'' = k(''a'' '''x''' ''b'') * ''a'' '''x''' ''a'' = 0 ---- What do you get if you cross a sheep with a kangaroo?: A woolly jumper What do you get if you cross a mountaineer with a mosquito?: Nothing - you can't cross a scalar and a vector. ---- CategoryMath