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synsacrum

American  
[sin-sak-ruhm, -sey-kruhm] / sɪnˈsæk rəm, -ˈseɪ krəm /

noun

Ornithology.

plural

synsacra

  1. a dorsal ridge of bone in the pelvic region of birds, formed by the fusion of certain thoracic, lumbar, sacral, and caudal vertebrae.

Other Word Forms

Etymology

Origin of synsacrum

First recorded in 1900–05; syn- + sacrum

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.