in·​fill | \ ˈin-ˌfil \

Definition of infill

1 : material that fills in something (such as a hole or the spaces between a building's structural members) volcanic infill fiberglass infill The artificial turf being used contains infill that is made from recycled tires …— Greg Fitzpatrick It's framed with hand-hewn cypress posts and beams, though instead of … brick infill … the walls are formed from … a mixture of mud, moss, and animal hair that was once used by native Americans living in the area.— Amy R. Hughes
2 : new buildings constructed in the space available between existing structures Urban infill, a big theme these days in city planning, is essentially the opposite of "urban sprawl." As cities grow, planners are looking for ways to pack more people into places that are already developed.— Franklyn Cater often used before another noun St. Louis must be the infill capital of the nation. Liberally scattered over the city, especially in the older parts, you see clumps and blocks of new apartments, condominia and row houses tucked in among centenarian neighbors.— E. F. Porterinfill housing

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Other Words from infill

infill verb, transitive + intransitive infilled; infilling
… it was easier to achieve the vaults themselves by building them of a framework of ribs infilled with webs. — James F. O'Gorman Stump holes can be expected to infill with material from the pit walls and immediate vicinity … — Jonathan D. Phillips et al.

Examples of infill in a Sentence

Recent Examples on the Web

Before a 19th-century infill effort, Boston’s Back Bay neighborhood was exactly that—a bay. Adam Bonislawski, WSJ, "Land Goes from ‘Dirt Cheap’ to ‘Pay Dirt’," 19 July 2018 Originally built as a family home and photography studio, this 1,600-square-foot residence occupies the infill plot sitting under a 19th-century viaduct with still-active trains running above it. Alex Bazeley, Curbed, "Sculptural steel home built into a 19th-century railway bridge wants $1.4M," 9 July 2018 The council’s action came nearly a month after the Park Ridge Planning and Zoning Commission voted 6-1 against recommending infill restrictions and new requirements for Murphy Lake property owners. Jennifer Johnson,, "Park Ridge aldermen reject restrictions on Murphy Lake infill," 29 May 2018 Atop the sand and rock came AstroTurf's 3D3 playing surface, featuring a shorter, denser turf carpet that uses more fiber and requires less infill than other surfaces. Tim Newcomb, Popular Mechanics, "How Bristol Turned a Racetrack Into a College Football Stadium," 9 Sep. 2016 Adding an infill stop at Ivy City could address one of DC’s most notably transit deserts. Matthew Yglesias, Vox, "HQ2 is a perfect opportunity to massively upgrade the DC area’s commuter rail," 17 Nov. 2018 In all, more than 100,200 square feet of surface was prepped at a height of 1.5 inches, filled with more than 180,000 pounds each of silica and rubber infill. Tim Newcomb, Popular Mechanics, "How Bristol Turned a Racetrack Into a College Football Stadium," 9 Sep. 2016 Both of those paths would extend under the Lake Shore Drive bridge to the 3.3-acre parcel of infill near the river’s mouth that long has been planned as DuSable Park. Bill Ruthhart,, "Exclusive: Two soaring towers planned for long-languishing Chicago Spire site along Lake Shore Drive," 11 May 2018 The City Council on May 21 voted 5-1 against amendments to the city’s zoning ordinance concerning the infill of Murphy Lake, a manmade lake surrounded by 33 residential properties. Jennifer Johnson,, "Park Ridge aldermen reject restrictions on Murphy Lake infill," 29 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'infill.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of infill

1939, in the meaning defined at sense 1

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Last Updated

7 Jan 2019

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Time Traveler for infill

The first known use of infill was in 1939

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