INFILL
Etymology 1
Verb
infill (third-person singular simple present infills, present participle infilling, simple past and past participle infilled)
To fill in a space, hole or gap.
To rededicate land in an urban environment to new construction.
Noun
infill (plural infills)
That which fills in a space, hole or gap.
(cosmetics) The redecoration of a fingernail or toenail after it has grown, to prevent an unsightly gap.
Etymology 2
Apparently by shortening.
Noun
infill
(uncommon, especially, military) Infiltration, the act of going into a place.
Antonyms
• exfill
Anagrams
• fill in, fill-in, fillin'
Source: Wiktionary