proof plane

11 LETTERS · STARTS WITH P

proof plane is a valid 11-letter word worth 17 points in Scrabble and 21 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS

P3R1O1O1F4P3L1A1N1E1

3 + 1 + 1 + 1 + 4 + 0 + 3 + 1 + 1 + 1 + 1 =17 PTS

DOUBLE WORD → 34TRIPLE WORD → 51

MEANING

What does proof plane mean?