The Volvo symbol, a circle with an arrow, is commonly mistaken for the Male-gender astronomical sign, but it is actually the chemical symbol for the element Iron.
Volvo are a Swedish company and the iron trade was a huge source of income for the country. Not only that, but the iron was well known for being high quality, strong and hardwearing and that is part of the identity Volvo tried to create through their branding.
Confusing the Male symbol and the Iron symbol is an easy mistake to make as both are actually the same, having originally come from the symbol for the war god Mars. It is a battle insignia and represents a shield and an arrow.
This article shows the surprising origins of 10 other car company logo's: http://www.businessinsider.com/car-logos-2011-5?op=1
And here is more information about the gender symbols if you were interested: //references-definitions.blurtit.com/177701/what-is-the-symbol-for-male-and-female
