Several people have mentioned this trio to me, so it’s time to set it all out and explain it …
Lighting is the system or arrangement of lights, in a home or a theatre or film studio or wherever there are lights, or the effect that this arrangement has – “The lighting in the scene gives a feeling of doom”.
Lightening means becoming lighter in weight – “He was lightening the balloon by throwing out the ballast, and we went up, up and away!” or paler in colour – “She’s been lightening her hair again”. It also has a technical, gynaecological meaning to do with wombs: you can look that up yourselves, as I think that’s one of those terms that you will know if you need to know it.
Lightning is the visual presentation of the electrical discharge between clouds, or between clouds and objects, during a thunderstorm. As a modifier, it also means very quick, linking of course to the very quick nature of lightning itself, as in, “His lightning reflexes meant he caught the pint glass before it hit the floor”.
You can find more troublesome pairs here and the index to them all so far is here.
LibroEditing proofreading, editing, transcription, localisation 
NightHawk
May 28, 2013 at 11:12 am
Great answer, thank you ; )
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Pedro
September 11, 2015 at 6:13 pm
Great explanation. Simple and spot on!
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vikram
February 8, 2016 at 2:57 pm
Really very good explanation.
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Kiran
February 24, 2016 at 6:06 am
Superb! Thanks,
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Amit Dey
November 28, 2016 at 5:12 pm
which one is correct sentence……. the chief guest inaugurated the program lightening the lamp or lighting the lamp
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Liz Dexter
November 28, 2016 at 5:15 pm
It is correct to say “lighting the lamp”.
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Endawoke
March 29, 2019 at 12:01 am
Very important information though it seems simple… I am also observing Even Instructors making such an error.
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Liz Dexter
March 29, 2019 at 8:58 am
It is one that comes up quite a lot – hopefully if people know there’s an issue they will find posts like this one. Thank you for your comment.
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