Topband: !80 deg phase inverter vs Flip transformer

[Tom W8JI]

Been reading in ON4UN low band dxing book about mulitable element receive 
arrays for 160 meters. I'm a little confused about 180 deg phase inverters, 
and flip transformers are these two the same thing?
>>>>>

I never heard of "flip transformers" before, but in context of the 
application I immediately recognize it as different names for the same 
result. They invert, or rotate, signal phase 180 degrees over a wide 
frequency range.

Any reasonable name is acceptable as long as the text or context explains 
the function.