rule of grammar

NOUN
15 LETTERS · STARTS WITH R

rule of grammar is a valid 15-letter word worth 21 points in Scrabble and 26 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
R1U1L1E1O1F4G2R1A1M3M3A1R1
1 + 1 + 1 + 1 + 0 + 1 + 4 + 0 + 2 + 1 + 1 + 3 + 3 + 1 + 1 =21 PTS
DOUBLE WORD → 42TRIPLE WORD → 63
MEANING

What does rule of grammar mean?

NOUN · 1 SENSE
1

A linguistic rule for the syntax of grammatical utterances.