What It Scores
COSTUME is a valid word in the tournament list this site uses. Tile values only, before any premium square: 11 in Scrabble and 13 in Words With Friends. The letters break down as C3 O1 S1 T1 U1 M3 E1.
At seven letters this plays a whole rack, which is a bingo and worth 61 in Scrabble once the 50 point bonus lands.
Words Made From The Letters In COSTUME
145 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.
6 letter words (4)
5 letter words (28)
COMESCOMETCOMTECOMUSCOSETCOSTECOTESCUTESESCOTESTOCMEOUSMESTOMOSTEMOTESMOTUSMOUESMOUSEMOUSTMUSETMUTESSCOUTSCUTESMOTESMOUTSOUCESOUCTTOMESTOUSE
4 letter words (53)
COMECOMSCOSECOSTCOTECOTSCUESCUTECUTSECOSECUSEMOSEMUSMEOUMETSMEUSMOCSMOESMOSEMOSTMOTEMOTSMOTUMOUEMOUSMUSEMUSOMUSTMUTEMUTSOUSTOUTSSCOTSCUMSCUTSECOSECTSOMESOUMSOUTSTEMSTUMSUETSUMOTECSTEMSTOCSTOESTOMETOMSTOSETUMSUTES
3 letter words (43)
COSCOTCUECUTECOECUEMOEMSEMUESTMESMETMEUMOCMOEMOSMOTMOUMUSMUTOESOMSOSEOUSOUTSECSETSOCSOMSOTSOUSUESUMTECTESTOCTOETOMTUMUMSUSEUTEUTS
2 letter words (17)
Next: the Word Unscrambler for any letters at all. Full entry and definition at Merriam-Webster.