Grammar help?

Both un and dis come from Old English (Germanic) but they originally have different meanings.

un means “no”

dis means “apart”

So actually, “dis” refers to an idea in opposition to, I like to imagine dis is fighting with whatever word it’s next to.

un refers to not that idea, so an un word is not as aggressive or strong as a dis word.

Example:

To be uninterested means that you’re not interested

To be disinterested means that your purposely not interested, you’re trying to be the opposite.

Basically there isnt any trick to remembering whether to use prefix ‘un’ and ‘dis’. It’s whether you are willing to learn and also whether you read widely. You can search for these meanings in the COBUILD dictionary. I guess if you keep pronouncing the word for say around 5 times it should be able to get into your head.

I believe that there’s no trick here. Practice can help only.

The difference between them is too small to see it. In some words I can explain it – when you add them to the same stem. But there’s no universal rule.

m-w.com is Merriam Webster’s dictionary. Try it.

“Un” means “not.”

“Dis” means “opposite.”

That is, “unorganized” means “not organized’ while “disorganized” means “messy.”