Answer:

thumb

Answer	Crossword Clue
THUMB	Green finger?
THUMB	Pollex
THUMB	Hitchhiker's important digit

THUMB	Hitchhike
THUMB	Hitch
THUMB	Hitchhiker's aid
THUMB	Opposable digit
THUMB	Hitchhiker identifier
THUMB	Twiddled digit
THUMB	Word before screw or tack
THUMB	Hand part

THUMB	A gardener's might be green
THUMB	Seek a ride
THUMB	Try to catch, as a ride
THUMB	Tiny Tom
THUMB	Hitchhiker's digit
THUMB	Mitten part
THUMB	Thing that points downward for a dog
THUMB	Green digit?

THUMB	Hitching aid
THUMB	Try to catch a ride
THUMB	Hitcher's digit
THUMB	Hitchhiker's need
THUMB	Hitchhiker's finger
THUMB	Try for a ride
THUMB	Hitchhiking need
THUMB	Snapping need

THUMB	Use this in hiking.
THUMB	Queen Victoria entitled him "General" Tom.
THUMB	Hitchhiker's prop.
THUMB	Hitchhiker's stock in trade.
THUMB	Solicit a ride.
THUMB	Pollex.
THUMB	Digit.
THUMB	Tom ....

THUMB	Road sign of a kind.
THUMB	Hitchhiking aid
THUMB	Kind of screw or tack
THUMB	Kind of screw
THUMB	... a ride (hitchhike)