ACCIDENT - [noun] something unpleasant and damaging that happens unexpectedly or without intention
Examples of use
There is a huge traffic jam on the motorway, because there has been an accident.
Don't be angry with me! It was just an accident.
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English speaking practise
Remember that if you don't use that word in English conversations or writing you'll forget it in a short time. So the best thing you can do to learn this word is just trying to use it in speaking or writing. Remember also that practise is the key to fluent english speaking.
You can always find a partner, who would also like to improve his/her