What It Scores
JAY is a valid word in the tournament list this site uses. Tile values only, before any premium square: 13 in Scrabble and 15 in Words With Friends. The letters break down as J8 A1 Y4.
Words Made From The Letters In JAY
3 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 (3)
Longer Words Containing JAY
JAY 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.