Break off seems to be one of those "old military" phrases that has crept into the civilian area, if you ask me. There is no real ICAO definition of it (or is there?)
I don't use it but will either tell a pilot to go around, when I want them to fly the MAP, or if I need to terminate the approach and reposition him, I prefer to say "xxx for repositioning ........." Seems to work well for me and I have not had any problems.