Answer:

zero

Answer	Crossword Clue
ZERO	Nil
ZERO	With no value
ZERO	Gravity or hour leader

ZERO	Love, in tennis
ZERO	Nothing
ZERO	Round figure
ZERO	Calibration setting
ZERO	Round figure?
ZERO	Round number?
ZERO	Celsius freezing point
ZERO	What's before one

ZERO	Matthew : Nathan :: Gene : ..
ZERO	Goose egg
ZERO	"The Adding Machine" protagonist
ZERO	Number with no multiplicative inverse
ZERO	Mitsubishi ... (WWII attack plane)
ZERO	Main character of Elmer Rice's "The Adding Machine"
ZERO	Japanese fighter plane
ZERO	Nada

ZERO	Losing score
ZERO	Round number
ZERO	Zip
ZERO	Nonentity
ZERO	Zilch
ZERO	Blank tile value, in Scrabble
ZERO	Celsius temperature at which water freezes
ZERO	You can't divide by it

ZERO	Coldest possible temperature on the Kelvin scale
ZERO	Freezing point, on the Celsius scale
ZERO	None
ZERO	-
ZERO	Reset, as an odometer
ZERO	Home (in)
ZERO	Half of 10?
ZERO	Reset

ZERO	World dodo population
ZERO	Diddly
ZERO	It means nothing
ZERO	Nothing at all
ZERO	Squat