decussate

[ adjective dih-kuhs-eyt, -it; verb dih-kuhs-eyt, dek-uh-seyt ]

adjective

1. in the form of an X ; crossed; intersected.
2. Botany. arranged along the stem in pairs, each pair at right angles to the pair next above or below, as leaves.

verb (used without object)

, de·cus·sat·ed, de·cus·sat·ing.

1. to intersect; cross in the form of an X :

   About 75 percent of these nerve fibers decussate in the medulla.

decussate

verb

1. to cross or cause to cross in the form of the letter X; intersect

adjective

1. in the form of the letter X; crossed; intersected
2. botany (esp of leaves) arranged in opposite pairs, with each pair at right angles to the one above and below it

Derived Forms

• deˈcussately, adverb
• ˌdecusˈsation, noun

Other Words From

• de·cus·sate·ly adverb

Word History and Origins

Origin of decussate¹

First recorded in 1650–60; from Latin decussātus “divided in the form of an X” (past participle of decussāre ), equivalent to Latin decuss(is) “the numeral ten,” originally, “a ten-as weight,” supposedly from unrecorded dec(-em) assis ); ten, as ², -ate ¹

Word History and Origins

Origin of decussate¹

C17: from Latin decussāre, from decussis the number ten, from decem ten

Example Sentences

Fertile catkins globular, of shield-shaped scales decussate in pairs, bearing few (1–4) erect bottle-shaped ovules at base.

From Project Gutenberg

A Melaleuca with very small decussate leaves, a tree about twenty-five feet high, was growing on the scrubby ridges.

From Project Gutenberg

The whorls or pairs alternate or cross each other, usually at right angles, that is, they decussate.

From Project Gutenberg

The remaining fibres pass down as the direct pyramidal tract, and decussate in the cord near their termination.

From Project Gutenberg

Thus, leaves normally opposite and decussate may, by fusion, become alternate.

From Project Gutenberg

Related Words

• cross
• cut across