used to mean ‘fairly’ or ‘to some degree’, often when you are disappointed, surprised or expressing slight criticism 

used with a verb to make a statement sound less strong

I've always rather liked Charlie.

I rather suspect we're making a mistake.

We were rather hoping you'd be able to do it by Friday.

used to correct something you have said, or to give more accurate information

She worked as a secretary, or rather, a personal assistant.

In the end he had to walk—or rather run—to the office.

used to introduce an idea that is different or opposite to the idea that you have stated previously

The walls were not white, but rather a sort of dirty grey.

The problem is not in the whole system, but rather in one small part.

used to agree with somebody’s suggestion

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