What It Scores
KI is a valid word in the tournament list this site uses. Tile values only, before any premium square: 6 in Scrabble and 6 in Words With Friends. The letters break down as K5 I1.
Longer Words Containing KI
KI 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.