nuchal

plural nuchals

1. The back of the neck.

   Synonyms: nape, nucha

2. abbreviationcolloquialellipsismedicineEllipsis of nuchal translucency scan.
3. biologyA neck scale, especially of a lizard.

   Growth patterns of clavicles, cleithra, opercles, medial nuchals, dorsal scutes, and pectoral fin ray sections have been compared in white sturgeon Acipenser transmontanus.

   2004, B.G. Kapoor, Bhavna Khanna, Ichthyology Handbook, page 248

   2 more examples

   Dunn gives a key to a part of this group of Eumeces, based upon the number of nuchals, placing the two American species (he does not consider Eumeces altamirani Dugès) in a group having 14-17 pairs of nuchals;[…].

   1935, The Kansas University Science Bulletin, volume 23, page 105

   Scales are weakly differentiated, with head scales flat and smooth, nuchals small and smooth, dorsal scales small and keeled, and tail scales larger ventrally than laterally, without wings.

   2004, Hans-Georg Horn, “6.19: Varanus salvadorii”, in Eric R. Pianka, Dennis R. King, Ruth Allen King, editors, Varanoid Lizards of the World, Indiana University Press, page 236

1. not comparableOf or pertaining to the back or nape of the neck.

   Many particulars of the nuchal torus region and nuchal plane are preserved (see Caspari, 1991 for further details, our description replies heavily on Caspari's work).

   2006, David W. Frayer, Jan Jelinek, Martin Oliva, Milford H. Wolpoff, “Chapter 9: Aurignacian male crania, jaws and teeth from the Mladeč Caves, Moravia, Czech Republic”, in Maria Teschler-Nicola, editor, Early Modern Humans at the Moravian Gate: The Mladec Caves and their Remains, Springer, page 220

   2 more examples

   What is the differential diagnosis of increased nuchal thickness? Although most fetuses with increased nuchal thickness are normal, the differential diagnosis of increased nuchal thickness includes an increased risk of fetal aneuploidy, particularly trisomy 21.

   2004, Vikram Dogra, Deborah J. Rubens, Ultrasound Secrets, Hanley & Belfus, page 58

   Nuchal thickness was the first sonographic marker associated with an increased risk of trisomy 21 in the fetus and is now accepted as the single most sensitive and specific marker for the detection of DS in the second trimester, in high- and low-risk pregnancies.

   2006, A. Antsaklis, “Ultrasonographic soft markers for chromosomal abnormalities”, in Asim Kurjak, Frank A. Chervenak, editors, Textbook of Perinatal Medicine, 2nd edition, Informa Healthcare, page 1192