It's believed that askew was formed simply by attaching the prefix a- (meaning, among other things, "in (such) a state or condition") to skew.

Which of these terms means askew?

adjective. crooked; awry: Your clothes are all askew.

Is askew a real word?

Although it sounds like a sneeze, the word askew means lopsided or turned and tilted to the side. Like your glasses might be after, well, a sneeze. Anything askew is crooked. The word askew probably comes from Old Norse for "on a skew," or "to turn aside." No matter how you look at it, anything askew is at an angle.