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sense

(Encyclopedia)sense, faculty by which external or internal stimuli are conveyed to the brain centers, where they are registered as sensations. Sensory reception occurs in higher animals through a process known as t...

absolute zero

(Encyclopedia)absolute zero, the zero point of the ideal gas temperature scale, denoted by 0 degrees on the Kelvin and Rankine temperature scales, which is equivalent to −273.15℃ and −459.67℉. For most gase...

indigestion

(Encyclopedia)indigestion or dyspepsia, discomfort during or after eating caused by some interference with the normal digestive process. Symptoms include nausea, heartburn, abdominal pain, gas distress, and a feeli...

Lowe, Thaddeus Sobieski Coulincourt

(Encyclopedia)Lowe, Thaddeus Sobieski Coulincourt thădˈēəs sōˌbē-ĕsˈkē kōˈlĭnkôrtˌ lō [key], 1832–1913, American aeronaut and inventor, b. Coos co., N.H. He flew (1861) a distance of 900 mi (1,448...

fluid

(Encyclopedia)fluid, any substance that is able to flow. Of the four states of matter, only a solid is not a fluid, since it has a definite shape that is not readily changed. Any liquid, gas, or plasma is classed a...

Kaiser, Georg

(Encyclopedia)Kaiser, Georg gāˈôrkh kīˈzər [key], 1878–1945, German expressionist playwright. His early plays dealt with the erotic and the psychological. In maturity Kaiser turned to social themes, glorify...

lewisite

(Encyclopedia)lewisite lo͞oˈəsītˌ [key], liquid chemical compound used as a poison gas. Like mustard gas and nitrogen mustard, it is a blistering agent; when inhaled, it is a powerful respiratory irritant. The...

Brownian movement

(Encyclopedia)Brownian movement or motion, zigzag, irregular motion exhibited by minute particles of matter when suspended in a fluid. The effect has been observed in all types of colloidal suspensions (see colloid...

van der Waals, Johannes Diderik

(Encyclopedia)van der Waals, Johannes Diderik yōhäˈnəs dēˈdərĭk vän dər väls [key], 1837–1923, Dutch physicist. It had been known for some time that the behavior of real gases differs from that of an i...

post-traumatic stress disorder

(Encyclopedia)post-traumatic stress disorder (PTSD), mental disorder that follows an occurrence of extreme psychological stress, such as that encountered in war or resulting from violence, childhood abuse, sexual a...