"What is running water?" in respect to D&D vampires?

Rivers are running waters, used as an example in others editions. How about rain (no answers are accepted on the related question)? How about a bottle? How about peeing on a vampire? How about puddles?

Related question:

[Is rain considered Running Water for a Vampire's weakness?][1]

[Can the Tidal Wave spell trigger a vampire's weakness to running water?][2]


  [1]: https://rpg.stackexchange.com/questions/121610/is-rain-considered-running-water-for-a-vampires-weakness
  [2]: https://rpg.stackexchange.com/questions/147457/can-the-tidal-wave-spell-trigger-a-vampires-weakness-to-running-water