atrium cordis

NOUN
13 LETTERS · STARTS WITH A

atrium cordis is a valid 13-letter word worth 17 points in Scrabble and 20 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
A1T1R1I1U1M3C3O1R1D2I1S1
1 + 1 + 1 + 1 + 1 + 3 + 0 + 3 + 1 + 1 + 2 + 1 + 1 =17 PTS
DOUBLE WORD → 34TRIPLE WORD → 51
MEANING

What does atrium cordis mean?