The name Njordur is related to the IndoEuropean words that mean hard or tough, as Nero, which means strong and brave.
Njordur was a god of fertility, winds, sea, fishing, wealth and summer. Later Freyr took over as god of fertility but Njordur became the god of sailors and fishermen. Maybe Njordur was originally the brother of an ancient godess, Nerthus, who was worshipped in Denmark as a symbol of Mother Earth.
In Heimskringla (Orbit of the World, by Snorri Sturluson) it says that Njordur had his children, Freyr and Freyja, with his sister, which was common by Vanir but not by Aesir. But in Snorri's Edda Njordur is married to Skadi.
In Iceland two places are called Njardvik, one near Reykjavik and the other in the east of the country. In Reykjavik and near you can find the streetnames like Njardargata, Njardargrund, Njardarholt and Noatun (which was the name of Njordur's dwellings).
