What It Scores
YUM is a valid word in the tournament list this site uses. Tile values only, before any premium square: 8 in Scrabble, 9 in Words With Friends, 9 in Wordfeud. The letters break down as Y4 U1 M3.
Words Made From The Letters In YUM
4 shorter words come out of these tiles. On a board that matters more than the long play, because a short word on a premium square often beats a long one on plain squares.
2 letter words (4)
Longer Words Containing YUM
YUM appears inside each of these, which is what makes it worth knowing as a hook.
Next: the Word Unscrambler for any letters at all, and the two and three letter lists. Full entry and definition at Merriam-Webster.