back and forth

Short definition from Wiktionary

Adverb

1. 1
   From one place to another and back again.

Adjective

1. 1
   Going from one place or position to another and back again.

Noun

1. 1
   The movement (of someone or something) forward followed by a return to the same position. May refer to a concept such as an emotional state or a relationship as well as a physical thing.
2. 2
   Negotiations or discussions (not necessarily fruitful) between two or more parties; a dialog.
3. 3
   Alternative form of back and forth.