missing link

American  

[mis-ing lingk] / ˈmɪs ɪŋ ˈlɪŋk /

noun

1. a hypothetical form of animal assumed to have constituted a connecting link between the anthropoid apes and humans, identified by some authorities as constituting the genus Australopithecus.

2. something lacking for the completion of a series or sequence.

   It’s tricky to find the missing link between children’s books and adult fiction.

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missing link British  

noun

1. (sometimes capitals) a hypothetical extinct animal or animal group, formerly thought to be intermediate between the anthropoid apes and man

2. any missing section or part in an otherwise complete series

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missing link Cultural  

1. A supposed animal midway in evolution between apes and humans. The term is based on a misunderstanding about the theory of evolution, which does not state that humans are descended from apes, but rather maintains that both humans and apes descended from a common ancestor. Modern evolutionary scientists do not search for a “missing link.”

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Etymology

Origin of missing link

First recorded in 1850–55

Example Sentences

See Examples For:

missing link

"The timeframe of our discoveries fills a geological gap or missing link present in records of other countries," said Suravech Suteethorn, deputy director of the university's Palaeontological Research and Education Centre.

From Barron's ● Sep. 3, 2026

“Talladega Nights” pegs this missing link between America’s urban past and its exurban future from its opening seconds, putting a quote about “hot, nasty, badass speed” in the mouth of New York Swell Eleanor Roosevelt.

From Salon ● Aug. 16, 2026

Dulles came to believe that religion, specifically an ecumenical Protestantism aiming to promote cooperation among different sects, was the missing link that could provide a moral architecture for the global system.

From The Wall Street Journal ● Apr. 15, 2026

"Understanding human exposure to these chemicals may help explain a missing link in how some neurological diseases arise."

From Science Daily ● Mar. 25, 2024

This was the missing link in Darwin's logic: reproductive incompatibility, ultimately derived from genetic incompatibility, drove the origin of novel species.

From "The Gene" by Siddhartha Mukherjee