'Onus', it's A Big Word

Just Imagine if you did a typo error and change O to A, must be hilarious sentence.

I'm reading some contract today and came across this word - "ONUS", it sounds like 'you-know-what'.

So the definition:

o·nus

   

[oh-nuhs] 

–noun, plural o·nus·es.

1.

a difficult or disagreeable obligation, task, burden, etc.

2.

burden of proof. 

3.

blame or responsibility.

Note: Important word!