It has been said that this name is probably of unknown Greek origin. After looking at it for a while is saw the word RIPPA , which means riverbank and which is related to our own word, RIVER. Then, I noticed that the start of the word, AGR , which may be the truncated version of AGER, which means field , and which is related to our word ACRE.
In sum. the two parts make up the expression FIELD AND STREAM . So we have it ; Augustus was aided in war by Admiral FIELDnSTREAM! (or so it seems to me)