Cobber. A friend, a companion. Also used as a form of address (g'day cobber!).
Aussie Slang: I really like our Slang words we use, and so for those of us who know them this is just a little tribute and for those who have never heard or seen these words well welcome to Australia and our slang.
Feel free to add on to this series, just keep the Formatting at the start of the name of the cache “Aussie Slang # (insert number here)”