Oxymora. What ra?

While I was writing the post on 'Colourful Black Horse', I googled the word ‘oxymoron.’ Apart from Wiki, which gave me the title of this post Oxymora – rarely used plural of ‘oxymoron’ - there is this interesting site www.oxymorons.info.

So many oxymorons are listed on this site under various categories such as Newly added, Top favorites, Daily oxymoron, etc, and also under various subjects such as Arts, Business, Religion, and so on. We use many of these quite often without thinking of them as oxymorons.

Try these … Act normally, fighting for peace, final draft, vaguely aware, jumpo shrimp, …

But why are these considered oxymora – Labor Day, Life Insurance, etc. I don’t know. :-)