Master-Student Kamehameha (師弟かめはめ波 Shitei Kamehameha, lit. "Master and Apprentice Kamehame Waves") is Goku, Krillin, and Master Roshi's combined Kamehameha that they use in Dragon Ball Z: The World's Strongest.
When they use it, Goku, Krillin, and Master Roshi each charge their own Kamehameha. Then, they fire them at the same time so that the three energy waves merge into a large Kamehameha, inflicting a huge amount of damage.
In The World's Strongest, Goku, Krillin, and Master Roshi use this attack during the battle against Dr. Wheelo. However, it does not have any effect as his metal armor enables him to easily withstand the blast.