vertical engine

15 LETTERS · STARTS WITH V

vertical engine is a valid 15-letter word worth 20 points in Scrabble and 26 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS

V4E1R1T1I1C3A1L1E1N1G2I1N1E1

4 + 1 + 1 + 1 + 1 + 3 + 1 + 1 + 0 + 1 + 1 + 2 + 1 + 1 + 1 =20 PTS

DOUBLE WORD → 40TRIPLE WORD → 60

MEANING

What does vertical engine mean?