What do the following words have in common?

SIMULTANEOUS
VALIDATE
SOOTHE
REACH
SAVE
OUTLINE

HINTS:
It has to do with synonyms.

Answer:

Each word has a synonym beginning with CON:

CONCURRENT
CONFIRM
CONSOLE
CONTACT
CONSERVE
CONTOUR


Credit: GAMES Magazine
November, 2005
Liz Stoffel
CON FRONTATIONS  (adapted)