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

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

And first-time buyers, long a missing link of the housing market, represented some 34% of February sales, one of the highest rates in five years, according to National Association of Realtors data.

From Barron's • Mar. 14, 2026

He's the missing link between Jeff Buckley and Harry Styles.

From BBC • Jan. 7, 2026

“The missing link at this point, from my perspective, is the partnership with the parents and the families,” board member Judy Manouchehri said.

From Los Angeles Times • Mar. 3, 2024

In 1941, three years before Avery’s landmark experiment, two scientists, George Beadle and Edward Tatum, working in a basement tunnel at Stanford University, discovered the missing link between genes and physical traits.

From "The Gene" by Siddhartha Mukherjee