acephalous

American  

[ey-sef-uh-luhs] / eɪˈsɛf ə ləs /

adjective

1. Zoology. Also acephalic headless; lacking a distinct head.

2. without a leader or ruler.

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acephalous British  

/ əˈsɛfələs /

adjective

1. having no head or one that is reduced and indistinct, as certain insect larvae

2. having or recognizing no ruler or leader

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Etymology

Origin of acephalous

1725–35; < Greek aképhalos; see a- ⁶, -cephalous

Explanation

Anything that is acephalous is headless — like the acephalous horseman of folklore. The term acephalous refers to organisms that lack a head, or to a group or society with no leader, or "head." Clams, oysters, mussels, and scallops are acephalous, as are sea stars, sea urchins, and sponges. Some historical tribal societies were acephalous: they had no one formal, decision-making authority. Leaderless digital communities and music bands are acephalous. The term is also used in poetry: An acephalous line is missing its first syllable based on an expected metrical pattern — e.g., "da-DUM da-DUM" becomes "DUM da-DUM." The term acephalous comes from Greek, where a- means "without" and kephalē means "head."

Example Sentences

Geoffroy St. Hilaire has read a memoir of some length to the Academy of Sciences, on an acephalous mummy.

From North American Medical and Surgical Journal, Vol. 2, No. 3, July, 1826 by Bache, Franklin

They are like oysters, with extreme stress of shell, and only a blind, soft, acephalous body within.

From The Atlantic Monthly, Volume 09, No. 54, April, 1862 by Various

In the acephalous molluscs, the great development of the mantle of these molluscs has rendered their eyes and even their head entirely useless.

From Lamarck, the Founder of Evolution His Life and Work by Packard, A. S. (Alpheus Spring)

Does psychometry compare with astronomy and geology in its scientific rank, or does it compare with the acephalous biology, which occupies all medical colleges?

From Buchanan's Journal of Man, April 1887 Volume 1, Number 3 by Buchanan, Joseph R. (Joseph Rodes)

Such a cabinet ought not to be acephalous.

From The Life of William Ewart Gladstone (Vol 2 of 3) by Morley, John