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://www.encyclo.co.uk/visitor-contrib
   
   
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://www.encyclo.co.uk/visitor-contrib
   
   
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 Lat...
   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 crys...
    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. �...
    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://wordnetweb.princeton.edu/perl/web
    
    
14. precursor
    noun a substance from which another substance is formed (especially by a metabolic reaction)
    Found on http://wordnetweb.princeton.edu/perl/web
    
    
15. 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.encyclo.co.uk/local/21001
    
    
16. 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
    
    
17. 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/
    
    
18. 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...
    Found on http://www.wordinfo.info/words/index/inf
    
    
19. precursor
    intermediate material used to form a final superconductor
    Found on http://www.electropedia.org/iev/iev.nsf/
    
    
20. precursor
    Type: Term Pronunciation: prē-kŭr′sŏr Definitions: 1. 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 ...
    Found on http://www.medilexicon.com/medicaldictio
    
    
21. Precursor
    In photochemistry, a compound antecedent to a pollutant. For example, volatile organic compounds (VOCs) and nitrogen oxides react in sunlight to form ozone or other photochemical oxidants. As such, VOCs and oxides of nitrogen are precursors.
    Found on http://www.4cleanair.org/glossary.html
    
    
22. Precursor
    A change in the geological or geophysical conditions that is a forerunner to earthquake generation on a fault. Precursors cannot reliably be recognized as such beforehand.
    Found on http://earthquakescanada.nrcan.gc.ca/inf
    
    
23. Precursor
    (chemistry) In chemistry, a `precursor` is a compound that participates in the chemical reaction that produces another compound. In biochemistry, the term "precursor" is used more specifically to refer to a chemical compound preceding another in a metabolic pathway. See also:
    Found on http://en.wikipedia.org/wiki/Precursor
    
    
24. Precursor
    (bird) `"Precursor"` is a controversial prehistoric bird genus from the Early date=November 2007-->. It was established based on fossils found in England, e.g. in the famous London Clay deposits. Three species have been named, but the supposed "genus" seems to be a ...
    Found on http://en.wikipedia.org/wiki/Precursor