reticular, a.
(rɪˈtɪkjʊlə(r))
[ad. mod.L. rēticulār-is, f. rēticulum: see prec. So F. réticulaire, It. reticulare, Sp. and Pg. reticular.]
1. Resembling a net in appearance or construction; consisting of closely interwoven fibres or filaments; net-like: a. Anat.
| 1597 Lowe Chirurg. (1634) 143 The nerve..doth dilate itselfe, and maketh the tunicke reticular. 1682 Gibson Anat. 12 There is spread over the surface of the skin, a certain mucous and reticular body. 1768–74 Tucker Lt. Nat. (1834) I. 388 The auditory nerves are represented to us by anatomists as expanded in a reticular form at the bottom of the ear. 1787 Phil. Trans. LXXVII. 389 This reticular net-work in the Seal is very coarse. 1805 Ibid. XCV. 5 The heart is always compacted together by a delicate reticular membrane. 1855 Owen Skel. & Teeth 6 A reticular disposition of the bony substance. 1876 Duhring Dis. Skin 22 The papillary layer merges into the reticular layer without distinct line of demarcation. |
b. In specific Anat. uses: (i) reticular tissue, tissue of the reticuloendothelial system which helps to form the framework of lymphatic tissue, bone marrow, and the tissue of the spleen and liver.
| 1848 Quain's Elem. Anat. (ed. 5) I. p. cxiii, The substance known by the names of ‘cellular’, ‘areolar’, ‘filamentous’, and ‘reticular’ tissue. 1892 H. E. Clark Wilson's Anatomist's Vade Mecum (ed. 11) i. 16 Reticular tissue is found in all lymphatic glands, in the pharynx and tonsils, the solitary and agminate glands of the intestine, the thymus gland, and in the spleen... From its presence in lymphatic glands it has been named ‘adenoid’ and ‘lymphoid’ tissue. 1941 Lancet 11 Jan. 46/1 The relationship of the angioid proliferations to the reticular tissue is..complex. |
(ii) Applied to a diffuse network of intermingled nerve fibres and nerve cell bodies in parts of the brain stem, one of the functions of which is to mediate changes in the degree of wakefulness.
| 1887 G. D. Thane Ellis's Demonstr. Anat. (ed. 10) ii. 197 In the dorsal portion of the medulla oblongata..the longitudinal fibres derived from the anterior and lateral columns of the cord..give rise to a structure that is known as the reticular formation of the medulla. 1949 Moruzzi & MaGoun in Electroencephalogr. & Clin. Neurophysiol. I. 455/1 The following account..explores the relations of this reticular activating system to the arousal reaction to natural stimuli. 1962 A. Huxley Island xi. 171 Animal experiments indicated that it affected the reticular system. 1968 Passmore & Robson Compan. Med. Stud. I. xxiv. 20/1 It seems that consciousness is determined by the activity of the reticular formation and many anaesthetics act particularly upon it. 1975 D. & I. Jordan tr. M. Zimmermann in R. F. Schmidt Fund. Neurophysiol. vii. 221 There is a constant ‘activating’ afferent flow from the reticular system to the cerebrum that controls the state of consciousness. Therefore, the term ‘reticular activating system’ is used to denote this functional property of the Formatio reticularis. |
(iii) reticular cell, a fibroblast or other unspecialized cell, esp. a phagocytic cell that helps to form the framework of the reticuloendothelial system and plays an essential role in blood formation; cf. reticulum cell s.v. reticulum 5.
| 1925 Strong & Elwyn Bailey's Text-bk. Histol. (ed. 7) iv. 75 Others maintain that the delicate fibers run in the peripheral cytoplasm (ectoplasm) of the reticular cells. 1927 Amer. Jrnl. Path. III. 523 Study of the so-called reticular cells of the spleen, lymph nodes and other organs show [sic] that they possess fibroglia fibrils and that they, therefore, are fibroblasts. Ibid. 525 There are no reticular cells other than fibroblasts. 1938 H. M. Carleton Schafer's Essent. Histol. (ed. 14) 48 The granular leucocytes, lymphocytes and monocytes are all derived from a columnar stem-cell called by Sabin the reticular cell. 1938 Jrnl. Path. & Bacteriol. XLVII. 461 The term ‘reticular cell’ was first introduced by Ribbert (1889) in describing the cells of lymphoid tissue to distinguish between the ‘endothelial cells’ of the lymph sinuses and the reticular cells proper. 1970 T. S. & C. R. Leeson Histology (ed. 2) vi. 105/1 Reticular cells may give rise to free macrophages, to early precursors of erythrocytes and leukocytes, and perhaps to other cell types. 1975 Jrnl. Path. CXVII. 119 The term reticular cell should be reserved for the dendritic reticular cell of Nossal et al. Ibid. 121 Reticular cell, a phrase with so many meanings as to be meaningless. |
c. In other applications.
| 1720 Phil. Trans. XXXI. 85 He found it intirely coagulated,..with a reticular Pellicle upon the Surface exposed to the Air. 1769 E. Bancroft Guiana 265 Contenting themselves either with the bark of trees, or the reticular covering of a coco-nut. 1796 Kirwan Elem. Min. (ed. 2) II. 83 Hepatic Pyrites..is found crystallized..or reticular. 1802–3 tr. Pallas's Trav. (1812) II. 403 It has..a slightly serrated, reticular leaf. |
2. Arch. Of masonry: Constructed of lozenge-shaped stones, bricks, etc., or of square pieces set diagonally instead of vertically.
| 1797 Encycl. Brit. (ed. 3) XVI. 140/2 This structure consists of small pieces of baked earth cut lozengewise,..and was called reticular, from its resemblance to fishing-nets. 1823 [see reticulated 2]. |
3. Resembling a net in effect or operation; intricate, entangled.
| 1818 Peacock Nightmare Abbey Wks. (1875) 366 Cutting the Gordian knot of his reticular envelopment. 1822 Byron Juan xii. lix, Yet many have a method more reticular—‘Fishers for men’, like sirens with soft lutes. 1883 Cent. Mag. Oct. 822/1 The law is blind, crooked, and perverse..; its administration is on the practice of by-gone ages, slow, reticular, complicated. |
4. Of or pertaining to the reticulum of a ruminant.
| 1923 G. H. Wooldridge Encycl. Vet. Med., Surg. & Obstetrics II. 1025/1 This operation [sc. rumenotomy]..is sometimes performed for exploratory purposes in obscure cases of ruminal, reticular, or omasal indigestion. 1966 Dalling & Robertson Internat. Encycl. Vet. Med. V. 2633 The reticular contents are liquid and offer no resistance to a thorough examination. |
Hence reˈticularly adv., like a net.
| 1835–6 Todd's Cycl. Anat. I. 382/2 It is owing to this reticularly arranged stratum of muscular fibres that the bladder..presents its peculiar irregular surface. 1875 Blake Zool. 331 In Retepora the polypary is..perforated reticularly. |