A Swordsmith was a person whose job was to create swords and other bladed weapons. One such group of swordsmiths were the Swordsmiths of Gedref, who crafted a pair of daggers that Agravaine gave to Arthur as a present. As the blades dulled during the journey, Agravaine asked Merlin to sharpen them for him (The Secret Sharer).
Camelot employed a Royal Swordsmith. When he wielded Excalibur, Uther was surprised that Arthur went to Tom the blacksmith rather than the Royal Swordsmith, Merlin then revealed that it was he who went to Tom (Excalibur).