good riddance
idiom

- said when you are pleased that a bad or unwanted thing or person, or something of poor quality, has gone

Cambridge Dictionaries

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The first thing to know about the expression "good riddance" is that it is by nature a cynical phrase. By expressing relief or delight that you have gotten rid of (more about the word "rid" a little later) something or someone, the implication is that the person or thing that has been eliminated is bad, unpleasant or simply unwanted.

The noun riddance - a deliverance from or removal of something unwanted or undesirable - is rarely used by itself and instead is mostly utilized in the imperative expression "good riddance." This was not always the case however. In the 16th and 17th centuries, riddance was a general purpose noun and meant deliverance from or getting rid of something. Shakespeare appears to be one of the first users of "good riddance," which he used in Troilus and Cressida.

In British English, this expression is often extended to "good riddance to bad rubbish" as a way to emphasise the negative quality of the thing or person being referred to.

Riddance stems from the verb "rid," meaning to free or deliver from something undesirable (I finally rid myself of our visitors!) It is frequently combined with "get" in the passive auxiliary form "get rid of" (I can't wait to get rid of my old car!). Rid is believed to stem from a Scandinavian source (perhaps the Old Norse ryðja) that meant to clear (such as a space, a piece of land) or set free.

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Practice OWAD in a conversation

"Their neighbours with the barking dog have moved to another town. GOOD RIDDANCE! they said."