defecation reflex

NOUN
17 LETTERS · STARTS WITH D

defecation reflex is a valid 17-letter word worth 32 points in Scrabble and 35 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
D2E1F4E1C3A1T1I1O1N1R1E1F4L1E1X8
2 + 1 + 4 + 1 + 3 + 1 + 1 + 1 + 1 + 1 + 0 + 1 + 1 + 4 + 1 + 1 + 8 =32 PTS
DOUBLE WORD → 64TRIPLE WORD → 96
MEANING

What does defecation reflex mean?