Look up: precursor

1. 
   Precursor
   In photochemistry, a compound antecedent to a pollutant. For example, volatile organic compounds (VOCs) and nitric oxides of nitrogen react in sunlight to form ozone or other photochemical oxidants. As such, VOCs and oxides of nitrogen are precursors.
   Found on http://www.epa.gov/OCEPAterms/
   
   
2. 
   Precursor
   The chemical element that changes due to enzymatic or physical pressure.
   Found on http://bse.airtime.co.uk/defb.htm
   
   
3. 
   precursor
   [n] - a person who goes before or announces the coming of another
   Found on http://www.webdictionary.co.uk/definitio
   
   
4. 
   precursor
   Substance from which another, usually more biologically active, substance is formed.
   Found on http://sis.nlm.nih.gov/enviro/iupacgloss
   
   
5. 
   Precursor
   Any chemical reactant which takes part at any stage in the production of a toxic chemical, including any key component of a binary or multicomponent chemical system.
   Found on http://www.chemicalglossary.net/definiti
   
   
6. 
   Precursor
   In metabolism, a chemical substance from which another chemical substance is formed
   Found on http://www.chemicalglossary.net/definiti
   
   
7. 
   Precursor
   Something that precedes, e.g., a sign or symptom that forewarns of another, such as muscle aching may be the precursor of a tremor.
   Found on http://james.parkinsons.org.uk/pdglossar
   
   
8. 
   Precursor
   Material from which carbon fiber is made by pyrolysis. Common precursors are polyacrylonitrile (PAN), rayon and pitch.
   Found on http://www.komprex.com/Glossary/index.ht
   
   
9. 
   Precursor
   Precursor: Forerunner. That which precedes or is derived from an available source. The term 'precursor' is applied to an inactive substance converted to an active one (such as an enzyme, vitamin, or hormone). The term 'precursor' applies to any chemical that is transformed into another. From the Latin 'praecursor,' composed of 'prae-' (or pre-), be ...
   Found on http://www.medterms.com/script/main/art.
   
   
10. 
    precursor
    any other radionuclide produced for radio-labelling of another substance prior to administration Category: Medicine • any part,or all,of the starting material from which a single crystal is grown.This may be material which undergoes one or more chemical reactions prior to the actual crystal growth step Category: Electrical engineering and energy • any radioactive nuclide wh...
    Found on http://www.mijnwoordenboek.nl/definition
    
    
11. 
    Precursor
    Pre·cur'sor noun [ Latin praecursor , from praecurrere to run before; prae before + currere to run. See Course .] One who, or that which, precedes an event, and indicates its approach; a forerunner; a harbinger. « Evil thoughts are the invisible, airy precursors of all the storms and tempests of the soul.» Buckminster. Syn. -- P ...
    Found on http://www.encyclo.co.uk/webster/P/146
    
    
12. 
    precursor
    Something that precedes. ... 1. <biochemistry> In biological processes, a substance from which another, usually more active or mature substance is formed. ... 2. In clinical medicine, a sign or symptom that heralds another. ... Origin: L. Praecursor = a forerunner ... (18 Nov 1997) ...
    Found on http://www.mondofacto.com/facts/dictiona
    
    
13. 
    precursor
    forerunner noun a person who goes before or announces the coming of another
    Found on http://wordnet.princeton.edu/perl/webwn?
    
    
14. 
    precursor
    noun a substance from which another substance is formed (especially by a metabolic reaction)
    Found on http://wordnet.princeton.edu/perl/webwn?
    
    
15. 
    Precursor
    `Precursor` or `Precursors` may refer to: *``Precursor (bird)``, a supposed genus of fossil birds that is actually a chimera *Precursor (chemistry), a compound that participates in the chemical reaction that produces another compound *Precursors (Jak and Daxter), a fictional alien race in the video game Jak and Daxter *`Precursor` (novel), a novel by C. J. Cherryh *Precursor (Star Control), a fictional alien race in the video game Star Control *...
    Found on http://en.wikipedia.org/wiki/Precursor
    
    
16. 
    precursor
    (pre´kәr-sәr) something that precedes. In biological processes, a substance from which another, usually more active or mature substance, is formed. In clinical medicine, a sign or symptom that heralds another.
    Found on http://www.mercksource.com/pp/us/cns/cns
    
    
17. 
    Precursor
    • (n.) One who, or that which, precedes an event, and indicates its approach; a forerunner; a harbinger.
    Found on http://thinkexist.com/dictionary/meaning
    
    
18. 
    precursor
    (L. praecursor a forerunner) something that precedes. In biological processes, a substance from which another, usually more active or mature substance is formed. In clinical medicine, a sign or symptom that heralds another.
    Found on http://users.ugent.be/~rvdstich/eugloss/
    
    
19. 
    precursor
    precursor 1. A person or thing that precedes, as in a job, a method, etc.; a predecessor. 2. A person, animal, or thing that goes before and indicates the approach of someone or something else; a harbinger: 'The budding of tree leaves is a precursor of spring.' 3. A chemical that is transformed into another compound; such as, in the course of a chemical ...
    Found on http://www.wordinfo.info/words/index/inf
    
    
20. 
    precursor
    That which precedes another or from which another is derived, applied especially to a physiologically inactive substance that is converted to an active enzyme, vitamin, hormone, etc., or to a chemical substance that is built into a larger structure in the course of synthesizing the latter. [L. praecursor, fr. prae-, pre- + curro, to run]
    Found on
    
    
21. 
    precursor
    intermediate material used to form a final superconductor
    Found on http://www.electropedia.org/iev/iev.nsf/