USS是United States Ship，意指「美国船舰」。这缩写专指美国海军的现役船舰，例如「钟云号」（USS Chung-Hoon）。在启用典礼前的船只会被冠上PCU（Pre Commissioning Unit，尚未服役单位），而退役的船只则不保留USS的称号。
英语百科
United States Ship USS
United States Ship (abbreviated as USS or U.S.S.) is a ship prefix used to identify a commissioned ship of the United States Navy and applies to a ship only while she is in commission. Before commissioning, she is referred to as "Pre-commissioning Unit" (PCU). After decommissioning, she is referred to by name, with no prefix. Non-commissioned Navy ships go by the prefix USNS, which stands for United States Naval Ship.