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

There is nothing more audacious in the poet's conception of the worm looking up towards humanity, than the naturalist's theory that the progenitor of the human race was an acephalous mollusk.

From Ralph Waldo Emerson by Holmes, Oliver Wendell

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)

The clerk was there; Mr. Higgleby, isosceles, flabby and acephalous as ever, was there; Tutt and Mr. Tutt were there; and Bonnie Doon, and the stenographer and the jury.

From By Advice of Counsel by Train, Arthur Cheney

The admirable phrase, "A man with a special subject," might have been invented on purpose for these acephalous species in the domain of literature and politics.

From A Woman of Thirty by Balzac, Honoré de

Almost all bivalve shells, or those of acephalous mollusca, are marine, about sixteen only out of 140 genera being fresh-water.

From The Student's Elements of Geology by Lyell, Charles, Sir