plumb rule

NOUN /pləm_rul/
10 LETTERS · STARTS WITH P

plumb rule is a valid 10-letter word worth 15 points in Scrabble and 22 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
P3L1U1M3B3R1U1L1E1
3 + 1 + 1 + 3 + 3 + 0 + 1 + 1 + 1 + 1 =15 PTS
DOUBLE WORD → 30TRIPLE WORD → 45
MEANING

What does plumb rule mean?

NOUN · 1 SENSE
1

A plumb line attached to a narrow board.