infill

American  

[in-fil] / ˈɪnˌfɪl /

Or in-fill

verb (used with object)

1. to fill in.

   The old stream beds have been infilled with sediment.

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noun

1. the planned conversion of empty lots, underused or rundown buildings, and other available space in densely built-up urban and suburban areas for use as sites for commercial buildings and housing, frequently as an alternative to overdevelopment of rural areas.

adjective

1. of, relating to, or involving the use of infill in urban planning.

   infill condominium projects; infill office buildings and retail space.

infill British  

/ ˈɪnfɪlɪŋ, ˈɪnfɪl /

noun

1. the act of filling or closing gaps, etc, in something, such as a row of buildings

2. material used to fill a cavity, gap, hole, etc

3. an acrylic gel application that fills in the gap between a false nail and the root of the real nail, which is created as the real nail grows

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Etymology

Origin of infill

First recorded in 1875–80; in- ¹ + fill

Example Sentences

Development first took hold closer to Center City, where demand was strongest, then moved outward in the 2010s into adjacent rowhouse neighborhoods, including Fishtown, as property values rose and more infill projects became financially viable.

From The Wall Street Journal • Jun. 11, 2026

That same timetable also should apply to certain urban infill projects, he said.

From Los Angeles Times • May 1, 2026

City Hall insisted the design followed Football Foundation guidance to contain rubber infill with raised barriers, boot brushes, matting and filtered drainage, which it said Natural England had not objected to.

From BBC • Mar. 6, 2026

Of the roughly 300 stores the company plans to open by 2035, about one-third are expected to be infill locations in existing markets.

From The Wall Street Journal • Feb. 5, 2026

Naught but the clay, as to a rapture fond Could he with fire of genius thus infill!

From The Optimist's Good Morning by Perin, Florence Hobart