Back-to-back and Unbroken

Back-to-back adjective - Following one after another without others coming in between.

Unbroken and back-to-back are semantically related. In some cases you can use "Unbroken" instead an adjective phrase "Back-to-back".

Unbroken adjective - Going on and on without any interruptions.

Back-to-back and unbroken are semantically related. Sometimes you can use "Back-to-back" instead an adjective "Unbroken".