Answer:

wider

Answer	Crossword Clue
WIDER	More outside, to an ump
WIDER	Broader
WIDER	Dentist's directive

WIDER	Dentist's request
WIDER	Comparatively spread out
WIDER	Dentist's urging
WIDER	Like EEE, vis- -vis EE
WIDER	Like two-lane roads, vis- -via one-lane roads
WIDER	Safer, as a road
WIDER	Like modern roads, vis- -vis older ones
WIDER	Hygienist's request

WIDER	Improved, perhaps, as a road
WIDER	Airbus A380, vis- -vis most other planes
WIDER	More expansive
WIDER	More spacious
WIDER	Of greater expanse
WIDER	Less narrow
WIDER	More roomy
WIDER	Dentist's order

WIDER	Dentist's word
WIDER	Greater in girth
WIDER	Farther astray
WIDER	"The Brain--is .. than the Sky": Dickinson
WIDER	Broader.
WIDER	Fuller.
WIDER	More extensive.
WIDER	More ample.

WIDER	Ampler
WIDER	More vast
WIDER	More extensive
WIDER	"Open ... please"
WIDER	Not so narrow
WIDER	Less limited
WIDER	What aging rockers get, perhaps
WIDER	Badly Drawn Boy "... Than a Smile"

WIDER	Request from the dentist
WIDER	More broad
WIDER	Dentist's request, perhaps
WIDER	More spacious, in a way
WIDER	More capacious, perhaps