meliorate

VERB /miljə,reɪt/
9 LETTERS · 4 SYLLABLES · STARTS WITH M

meliorate is a valid 9-letter word worth 11 points in Scrabble and 13 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
M3E1L1I1O1R1A1T1E1
3 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 =11 PTS
DOUBLE WORD → 22TRIPLE WORD → 33
MEANING

What does meliorate mean?