or head room
- clear vertical space, as between the head and sill of a doorway, the ceiling and floor of a room, or the ceiling of a vehicular passageway and a vehicle roof, as to allow passage or comfortable occupancy: over 7.5 feet of headroom in the attic; a covered bridge with limited headroom.
- clear vertical space above one’s head, as in a vehicle or room: plenty of headroom for passengers.
Examples from the Web for headroom
Even given the extraordinary growth off the high base it is putting up, Amazon still has plenty of headroom.Amazon Stock May Be Up, but the Company Still Doesn’t Make Any Money|Daniel Gross|October 25, 2013|DAILY BEAST
So the Treasury Department did some fancy footwork and found some headroom by halting payments into government pension plans.
This roof was level with the bank of the hedge and gave about four feet of headroom.
In order to get headroom there is 'trunk' 'rise' on the deck, as shown on the cross-section drawing, 18 in.Yachting Vol. 2|Various.
Plenty of headroom has always been my cry; I believe that where it is attended to there is very rarely an accident.Riding for Ladies|Mrs. Power O'Donoghue
The headroom between the subway roof and the surface of the street was 4.75 feet.The New York Subway|Anonymous
Rawson could have stood upright in it with easily another two feet of headroom to spare.Two Thousand Miles Below|Charles Willard Diffin