[puetzk]

The (beat) "drop" is genre term for a buildup of tension, sharp pause, and then suddenly resuming at greater intensity/tempo. Usually associated with EDM/dubstep.

E.g. https://www.youtube.com/watch?v=db5f-A-vSyw (drop at 0:45 seconds in the video, thought the countdown to New years that takes up most of the stage should make that obvious anyway)....

Thought it's certainly not a new thing - plenty of classical music has similar moments, e.g. the 3rd movement to Beethoven's 5th symphony: https://youtu.be/xAQFJ1YpFaI?t=279 ("drop" at 5:05 when the horns blast their way in...)