step function

13 LETTERS · STARTS WITH S

step function is a valid 13-letter word worth 19 points in Scrabble and 24 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS

S1T1E1P3F4U1N1C3T1I1O1N1

1 + 1 + 1 + 3 + 0 + 4 + 1 + 1 + 3 + 1 + 1 + 1 + 1 =19 PTS

DOUBLE WORD → 38TRIPLE WORD → 57

MEANING

What does step function mean?