Answer:

positive

Answer	Crossword Clue
POSITIVE	Greater than zero
POSITIVE	Word (suggested by the black shape in this grid's center) that can precede the answers to starred clues
POSITIVE	Certain

POSITIVE	Type of charge
POSITIVE	Categorical
POSITIVE	It's accentuated in song.
POSITIVE	Confident.
POSITIVE	Incontestable
POSITIVE	Confident
POSITIVE	100% sure
POSITIVE	Upbeat

POSITIVE	Absolutely certain
POSITIVE	Optimistic