de·cus·sate (dĭ-kŭsāt′, dĕkə-sāt′)
tr. & intr.v. de·cus·sat·ed, de·cus·sat·ing, de·cus·sates
To cross or become crossed so as to form an X; intersect.
1. Intersected or crossed in the form of an X.
2. Botany Arranged on a stem in opposite pairs, at right angles to those above or below: decussate leaves.
[Latin decussāre, decussāt-, from decussis, the number ten, intersection of two lines (from the Romans' use of X for the numeral 10), a ten-as coin : decem, ten; see dek in the Appendix of Indo-European roots + assis, as (coin).]
(click for a larger image)decussate
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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