on-again, off-again

or on-a·gain-off-a·gain

[on-uh-gen awf-uh-gen, of-, awn-]
See more synonyms for on-again, off-again on Thesaurus.com
adjective
  1. being in force or inoperative by turns, especially spasmodically and unpredictably: an on-again, off-again romance.

Origin of on-again, off-again

First recorded in 1945–50
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018