will-they-won't-they

adjective2

1. •
   Of or pertaining to a potential coupling between two people who share romantic chemistry, but whose relationship is threatened by uncertainty, external obstacles or internal strife.

   • Princess Sonja, the daughter of an Oslo fashion house director, married Crown Prince Harald last summer after a will-they-won't-they romance that had gone on for a decade. — 1968
2. •
   Of or pertaining to any situation in which there is an extended period of uncertainty.

   • Among the small producers, the West German companies Continental Gummi and Phoenix Gummi are in the middle of a will-they-won't-they merger dance. — 1971