divaricator

plural divaricators

1. biologyOne of the muscles that open the shell of a brachiopod; a cardinal muscle.

   Relaxation of the divaricator fibers and maximal contraction of the radial myofilaments, which put the medial basement membranes in tension, may cause medial bending in the hook supports and closing of the hook apparatus.

   2012, Issues in Biological and Life Sciences Research, page 688

   2 more examples

   The relative position of the adductor and divaricator impressions varies somewhat in different species of the genus, as we have already described; thus, in P. giganteus, P. longispinus, &c., the divaricators are situated immediately under and outside of the adductor, while in P. pustulosus, P. humerosus, &c., the adductor is located between the two divaricator impressions, as in the case of P. comoides.

   1862, Thomas Davidson, William Herbert Dalton, A Monograph of the British Fossil Brachiopoda, page 277

   The interior of the ventral valve differs from the dorsal one by having its divaricator scars much narrower, and its occlusor impressions closer at the anterior extremity, and leaving only a very small space between them for the two little scars which Mr. Hancock thinks might belong to the anterior extremity of the dorsal adjustor.

   1866, Palaeontographical Society - Volume 19, page 79

2. medicineA surgical device for spreading the surroundings and holding open the area in which one is operating.

   In 1987, Griffith12 proposed an endonasal sphenoidotomy through a sphenoethmoidal recess. Here it is also necessary to use a divaricator.

   2010, Edward R. Laws, Giuseppe Lanzino, Transsphenoidal Surgery, page 153

   2 more examples

   An operation case containing: 1. A tongue forceps. 2. Heister's gag. 3. Author's ringed gag. 4. Three Krishaber's tracheotomoy tubes for children and adults. 5. One divaricator of the commissure. 6. One divaricator of the molars. […]

   1917, Eugène-Louis Doyen, Surgical Therapeutics and Operative Technique - Volume 1, page 228

   The automatic divaricator is placed between the ribs and the operative field is expanded by rotating the lever of the automatic divaricator (see Figure 7.1).

   2024, Henri Kolani, Esophageal Cancer Surgery: Akiyama Procedure, pages 7-1