It has proved difficult to find an answer to this question
A quick concordance search of "horn" and you will find many different uses for the word. My center-column notes say "strength." But why? What is the Hebrew sense of this word?
Psalm 92:10 might give a clue:
But my horn shalt thou exalt like the horn of an unicorn: I shall be anointed with fresh oil.
Horns are strong, they are used for annointing, for calls to battle. I seem to be answering my own question, however, there seems to be a development of the horn in the Bible, especially in the beasts in Daniel 7 & 8.
The phrase "the son of my right hand" has several understandings, but they are more obvious since handedness is universal. I know what horn means, what does horn really mean?