As with most of these pairs, this idea came from one of my readers: how to distinguish between relative and relation. Well, basically, it’s a subtle one!
I looked these ones up in the Oxford Concise English dictionary. Relative is defined as “considered in relation or in proportion to something else”.
Relation is defined as the way in which two or more people or things are connected or related.
I see this as relative being about a comparison, and relation about a similarity.
So, you can say, “the relation between rain and snow is that they are both wet and cold; relative to snow, rain is wetter but less cold”.
As regards the other main meaning, a relative is a person connected to another by marriage or blood (I’d add or adoption or arrangement there to cover adoptions, step-families, etc.) and a relation is defined simply as “a relative”. Your sister is your relation, and also your relative.
Always nice to have some subtlety on a Monday …
You can find more troublesome pairs here.
LibroEditing proofreading, editing, transcription, localisation 
Cee 4
January 12, 2016 at 6:20 am
Well, I didn’t get the usage of both words quite well. Which is more appropriate when talking about family? I read in another book that relative is but some Nigerian authors use relation.
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Liz Dexter
January 12, 2016 at 9:48 am
You can use either to talk about family. In the UK, we’d be more likely to say “This is my relative, x” rather than “This is my relation”, but obviously Englishes do vary around the world. I can only really comment definitively in the blog about UK and, to an extent, US English. I hope this helps, though.
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Cee 4
January 16, 2016 at 6:46 am
Thanks ma’am. Here in Nigeria, we are to use British English because we were their colony. I will like to know more about you ma’am. I am interested in writing and your advice can be useful.
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