From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
The Bukujutsu (舞空術, Bukūjutsu; Literally meaning "Dance Sky Arts") is a supportive technique used by many fighters.
The user manipulates their ki so that they can levitate or fly with their feet. It is not shown in the anime that they can fly with any other body part except during the Majin Buu Saga when Son Gohan teaches Son Videl how to fly by manipulating ki using his hands.
The Bukujutsu was first seen during the first appearance of Puar and was first named at the 22nd Tenkaichi Tournament when Tenshinhan and Chaozu were seen flying (Turtle Hermit called it "overrated"). Soon, all of the other Z Warriors (apart from Yajirobe and Turtle Hermit) learned the technique.
Dragon Ball Z
Son Goku asked Piccolo if he could keep up with the Kinto Un in "Unlikely Alliance". The Namekian replied that his own flying technique was significantly different and better than the Bukujutsu used by the Z Warriors, allowing him to fly even faster than the Kinto Un.
Son Gohan taught Son Goten and Son Videl how to fly during the Great Saiyaman Saga. Son Gohan further explained that anyone with sufficient power and the proper training could learn the ability. Mister Satan tried to self-teach this technique, but failed miserably.
The way Son Gohan described the secret of Bukujutsu, one would assume that the flyer is putting their ki underneath themselves and forcing it down similar to an engine or helicopter pushing air down to rise from the ground.
- 舞 (bu) = dance
- 空 (kū) = sky
- 術 (jutsu) = arts