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## Main Question or Discussion Point

Hi all. I have a question that is more about definitions or language, rather than physics.

So (Euclidean) vectors used in Physics are "geometrical entities endowed with a magnitude and a direction".

At least this is what i find if I look up "vector" in english speaking websites.

My "problem" is that in Italy a vector is an object that is fully characterized by three rather than two properties (I think that the same is true in France).

The point is that "direction" means basically the line which the vector lies on, with no information about the "course" along that line. So both a vector and its opposite have the same direction in Italy, and you need to specify which way they point along that line, to completely define either of them. Hence the three properties: "intensità" (magnitude), "direzione" (the straight line) and "verso" (the "course" along that line).

I guess that the use of "direction" to denote an undirected line comes from pure mathematics or geometry. I think it has to do with the fact that two points select a straight line irrespective of the order, so lines do not have a direction.

Still, I am curious as to what would the correct English term be for "the way you can point along a straight line".

I used "course" above, but it is just a guess. Another guess would be "wise", like in clockwise... But I do not think that it is used by itself, with this meaning.

I know, sounds like a kind of idle question, but I'm curious.

Also, since part of the last-year physics classes are taught in English, I sort of need the word to provide a more accurate explanation. After years of hearing that a vector is characterized by three properties, italian are surprised that "english vectors" are characterized by just two properties.

Thanks a lot

Francesco

So (Euclidean) vectors used in Physics are "geometrical entities endowed with a magnitude and a direction".

At least this is what i find if I look up "vector" in english speaking websites.

My "problem" is that in Italy a vector is an object that is fully characterized by three rather than two properties (I think that the same is true in France).

The point is that "direction" means basically the line which the vector lies on, with no information about the "course" along that line. So both a vector and its opposite have the same direction in Italy, and you need to specify which way they point along that line, to completely define either of them. Hence the three properties: "intensità" (magnitude), "direzione" (the straight line) and "verso" (the "course" along that line).

I guess that the use of "direction" to denote an undirected line comes from pure mathematics or geometry. I think it has to do with the fact that two points select a straight line irrespective of the order, so lines do not have a direction.

Still, I am curious as to what would the correct English term be for "the way you can point along a straight line".

I used "course" above, but it is just a guess. Another guess would be "wise", like in clockwise... But I do not think that it is used by itself, with this meaning.

I know, sounds like a kind of idle question, but I'm curious.

Also, since part of the last-year physics classes are taught in English, I sort of need the word to provide a more accurate explanation. After years of hearing that a vector is characterized by three properties, italian are surprised that "english vectors" are characterized by just two properties.

Thanks a lot

Francesco