For those with even rudimentry Japanese,
you should be able to recognize that "Ichi"
means "one." Here's a word-by-word translation:

Ten - Sky, Heaven
Kai - Beneath, under
Chi - (Number) One
Bu - Martial Arts, fighting technique
Dou - Way of
Kai - Meeting

"Tenka" (Under heaven) is used to refer to
"the world," as everything in this world is
beneath the skies / under heaven.

"Budou" means martial arts, or "the way
(art) of fighting."

Putting the rest together, a fairly concise
translation of "Tenkaichi Budoukai"
would be "The World's Best Martial Artist
Tournament."

The 21nd Tenkaichi Budoukai:

Champion: Master Roshi (Kamesennin)
Runner-up: Son Goku

The 22nd Tenkaichi Budoukai:

Champion: Tien
Runner-up: Son Goku

The 23rd Tenkaichi Budoukai:

Champion: Son Goku
Runner-up: Piccolo

The Cell Game:

Champion: Son Gohan

The 24th Tenkaichi Budoukai:

Champion: Mr. Satan

The 25th Tenkaichi Budoukai:

Adult Division Champion: Mr. Satan
Adult Division Runner-up: No. 18
Children Division Champion: Chibi Trunks
Children Division Runner-up: Son Goten

Note: In all the tournaments to follow,
Mr. Satan is the champion, while Mr.Buu
is the runner-up.. Basically Mr. Satan cheats
in letting Mr. Buu fight with everyone else first,
and then to throw the match to Mr.
Satan.