[pahy-ran, pahy-ran] /ˈpaɪ ræn, paɪˈræn/
either of two compounds having the formula C 5 H 6 O, containing one oxygen and five carbon atoms arranged in a six-membered ring.
an unsaturated heterocyclic compound having a ring containing five carbon atoms and one oxygen atom and two double bonds. It has two isomers depending on the position of the saturated carbon atom relative to the oxygen
/ˌpaɪrəˈnɒmɪtə/ noun 1. (physics) another name for solarimeter
[pahy-ruh-nohs, -nohz] /ˈpaɪ rəˌnoʊs, -ˌnoʊz/ noun, Biochemistry. 1. any monosaccharide having a ring structure. pyranose py·ra·nose (pī’rə-nōs’, -nōz’) n. A cyclic form of a sugar in which an oxygen bridges two carbon atoms, thus forming a ring containing five carbon atoms and an oxygen atom.
[pir-uh-zin-uh-mahyd, -mid] /ˌpɪr əˈzɪn əˌmaɪd, -mɪd/ noun, Pharmacology. 1. a substance, C 5 H 5 N 3 O, used in the treatment of tuberculosis.
pyrazine (pĭr’ə-zēn’) Any of a group of organic compounds having a six-member ring in which the first and fourth atoms are nitrogen and the rest are carbon. Pyrazines are components of many important compounds, including pteridines, some vitamins and antibiotics, and numerous dyes called phenazines.