The phrase "Dag Hjalmar Agne Carl Hammarskjöld" refers to a specific person, not just a single English word. He was a Swedish diplomat who served as the Secretary-General of the United Nations from 1953 until his death in 1961. He is known for his significant contributions to peacekeeping and international diplomacy.
Dag Hammarskjöld is a significant historical figure in the field of diplomacy and international relations, particularly known for his efforts in peacekeeping through the United Nations.