A feeling of unity with a population near a subject. "The vibe" as of 2018 is an expression of a good atmosphere where you feel comfortable to do/say whatever you want. Mainly used under the influence of alcohol or other drugs to define the collective feeling of the squad or music. For reference look to hip hop icons like Post Malone, ASAP Rocky, Kodak Black, or Juice World.
"Yo this is playlist is the vibe right now"