1: The part of the mammalian body between the neck and the abdomen; also: its cavity in which the heart and lungs lie.n2: The middle of the three chief divisions of the body of an insect; also: the corresponding part of a crustacean or an arachnid.
A small, slender, rigid, needle- or thornlike spicule.
Any blade with a few short branches arising apically or subapically.
Subdivision of trunk proper, which is demarcated from the neck by the plane of the superior thoracic aperture and from the abdomen internally by the inferior surface of the diaphragm and externally by the costal margin and associated with the thoracic vertebral column and ribcage and from the back of the thorax by the external surface of the posterolateral part of the rib cage, the anterior surface of the thoracic vertebral column and the posterior axillary lines; together with the abdomen and the perineum, it constitutes the trunk proper. Examples: There is only one thorax.
The main middle section of the insect body comprising three thoracic rings: the pro-, the meso- and the metathoraces which are more or less well fused and cask-like sometimes having on the upper lateral part one of two pairs of wings, while on the ventrolateral part each thoracic ring bears a pair of legs.
Organismal subdivision of body that lies between the head and the abdomen [Wikipedia].
Subdivision of trunk proper, which is demarcated from the neck by the plane of the superior thoracic aperture and from the abdomen internally by the inferior surface of the diaphragm and externally by the costal margin and associated with the thoracic vertebral column and ribcage and from the back of the thorax by the external surface of the posterolateral part of the rib cage, the anterior surface of the thoracic vertebral column and the posterior axillary lines; together with the abdomen and the perineum, it constitutes the trunk proper[FMA].