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

But in its present acephalous condition it is but a fragment of science—a headless corpse, unfit to rank among complete sciences.

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

The great development of mantle in the acephalous molluscs has rendered eyes, and even a head, entirely useless to them.

From Evolution, Old & New Or, the Theories of Buffon, Dr. Erasmus Darwin and Lamarck, as compared with that of Charles Darwin by Butler, Samuel

The pearl-bearing oyster is of a more delicate nature than most of the other acephalous mollusca.

From Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 1 by Ross, Thomasina

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)

In the acephalous twin described by Béclard, no liver, spleen, stomach, or œsophagus could be discovered, and the intestinal tube commenced at the superior extremity of the body.

From Curiosities of Medical Experience by Millingen, J. G. (John Gideon)