Angus is derived from the Gaelic 'Aonghus', a compound of two words - “aon”, which means 'one', and “ghus”, which means 'choice'. When joined together it becomes 'unique choice'.
The name Clyde originates in Gaelic languages and means that the bearer comes from somewhere near the river Clyde. The actual meaning of the name Clyde however is obscure because it is so ancient as to even predate the Celtic language.