Answer:

widen

Answer	Crossword Clue
WIDEN	Dilate
WIDEN	Enlarge (as a roadbed)
WIDEN	Expand

WIDEN	Spread
WIDEN	Grow broad
WIDEN	Broaden
WIDEN	Add lanes to
WIDEN	Spread out
WIDEN	Enlarge, as a road
WIDEN	Add a lane to, say
WIDEN	Make broader, as a highway

WIDEN	Improve the road, in a way
WIDEN	Let out
WIDEN	Ream
WIDEN	Go from two to four lanes
WIDEN	Add a lane to
WIDEN	Change, as from two lanes to four
WIDEN	Change the channel?
WIDEN	Improve, as a road

WIDEN	Gain weight, maybe
WIDEN	Enlarge
WIDEN	Modernize, as a highway
WIDEN	Add a lane to, as a highway
WIDEN	Extend
WIDEN	Improve, as a highway
WIDEN	Make broader
WIDEN	Stretch

WIDEN	Add lanes to, as a highway
WIDEN	Add a lane to, perhaps
WIDEN	Open up
WIDEN	Expand.
WIDEN	Enlarge.
WIDEN	Extend.
WIDEN	Spread.
WIDEN	Improve, as a road.

WIDEN	Make larger.
WIDEN	Amplify
WIDEN	Expand laterally
WIDEN	Dilate; expand
WIDEN	Enlarge, in a way