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

“It’s kind of a missing link in the system, through a fairly densely populated part of the city,” Elkind said of the proposed K Line extension.

From Los Angeles Times

The critical missing link at present is a viable transitional government.

From The Wall Street Journal

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

"I'm reminded of the famous 'Lucy' fossil, one of our hominid ancestors that lived 3 million years ago and was one of the key 'missing links' between apes and humans," he said.

From Science Daily

"I lost all my confidence after my diagnosis and treatment, so to bring the three of us together again to complete the missing link in our journey has been such a healing process," she said.

From BBC