de·​cus·​sate | \ ˈde-kə-ˌsāt How to pronounce decussate (audio) , di-ˈkə-ˌsāt How to pronounce decussate (audio) \
decussated; decussating

Definition of decussate

 (Entry 1 of 2)


de·​cus·​sate | \ ˈde-kə-ˌsāt How to pronounce decussate (audio) , di-ˈkə-sət \

Definition of decussate (Entry 2 of 2)

: arranged in pairs each at right angles to the next pair above or below decussate leaves

Did You Know?


The history of decussate leads us back to the intersection of decem, a word meaning "ten," and ass-, a form that refers to a unit of weight and specifically to a copper coin cut to a half-ounce. In the Roman numeral system the number 10 is represented by X, an intersection of two lines. A man named Sir Thomas Browne coined decussate in the 17th century to discuss the crossing fibers that make up human anatomy-for instance, skin tissue. The word continues to be found primarily in scientific contexts today.

First Known Use of decussate


1658, in the meaning defined above


circa 1823, in the meaning defined above

History and Etymology for decussate


Latin decussatus, past participle of decussare to arrange crosswise, from decussis the number ten, numeral X, intersection, from decem + ass-, as unit — more at ace

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The first known use of decussate was in 1658

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Cite this Entry

“Decussate.” Dictionary, Merriam-Webster, Accessed 9 Jul. 2020.

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More Definitions for decussate


de·​cus·​sate | \ ˈdek-ə-ˌsāt How to pronounce decussate (audio) , di-ˈkəs-ˌāt How to pronounce decussate (audio) \
decussated; decussating

Medical Definition of decussate

: to intersect in the form of an X

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Rhyming Dictionary: Words that rhyme with decussate

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