TheBoost said:

Its usually some fun etymology behind it.A DISaster can happen, but never just an aster.

Aster-astro-stars.

DisASTER means bad stars, or basically that fate aligned to cause a catastrophe.

Hey, that's an interesting one and never occurred to me. I'm sure a bunch of words we take for granted because of their commonality fall into a similar categories...words like destroy. Now just by looking at it I can't see it, but its relative destruct is the process of breaking something: de- meaning undoing, -struct having to do with something's structure. You can also construct something, but once it's complete, it never is simply struct. Never even thought of that till just now. Wonder how many there are like that! :)