soft launch

Short definition from Wiktionary

Noun

1. 1
   The launch of a missile in such a way that the rocket motor ignites outside of the launch tube, ejecting the missile non-explosively.
2. 2
   The release of a product or service (particularly software) to a limited audience, often in order to gain data on the product's usage and acceptance by customers.
3. 3
   The subtle or ambiguous announcement of a romantic relationship, often via social media.

Verb

1. 1
   Alternative form of soft-launch.
2. 2
   To release (a product or service) to a limited audience.
3. 3
   To announce (a romantic relationship) or reveal (one's romantic partner) in a subtle or ambiguous manner.