Look up: radioactive

1. 
   Radioactive
   Radioactive elements are those of high atomic weight (radium, thorium, uranium etc.) which spontaneously emit alpha, beta or gamma rays.
   Found on http://www.encyclo.co.uk/nol.php
   
   
2. 
   Radioactive
   Radioactive can generally describe the property of a substance (or more accurately atomic nuclei) which are unstable and spontaneously Decay (disintegrate) with the release of energy, the energy being either Electromagnetic Radiation , particulate or both. This process may occur in both naturally occurring radioactive material and man made substances. For any given element there will be a number of Isotopes , some of which may be radioactive. The point at which a substances can be said to be radioactive requires careful interpretation of law and may depend on particular circumstances. For example, in the UK, material with an Activity < 0.4 Bq / g is not considered radioactive (Radioactive Substances Act 1993).
   Found on http://www.ionactive.co.uk/glossary_atoz
   
   
3. 
   radioactive
   [adj] - exhibiting or caused by radioactivity
   Found on http://www.webdictionary.co.uk/definitio
   
   
4. 
   Radioactive
   Possessing the property of radioactivity.
   Found on http://www.shponline.co.uk/glossary.asp?
   
   
5. 
   Radioactive
   A material is said to be radioactive if it emits radiation. Radioactive materials have unstable nuclei which have a tendency to decay. It is when a decay occurs that radiation is released from the nucleus. Important related concepts are the activity and half-life of a source
   Found on http://www.users.zetnet.co.uk/computing/
   
   
6. 
   radioactive
   Substance containing an element which decays.
   Found on http://www.shodor.org/UNChem/glossary.ht
   
   
7. 
   Radioactive
   Something which gives off high energy rays or particles.
   Found on http://www.cancerhelp.org.uk/glossary.as
   
   
8. 
   Radioactive
   Radioactive: Emitting energy waves due to decaying atomic nuclei. Radioactive substances are used in medicine as tracers for diagnosis, and in treatment to kill cancerous cells.
   Found on http://www.medterms.com/script/main/art.
   
   
9. 
   radioactive
   Giving off radiation. ... (12 Dec 1998) ...
   Found on http://www.mondofacto.com/facts/dictiona
   
   
10. 
    radioactive
    adjective exhibiting or caused by radioactivity; `radioactive isotope`; `radioactive decay`; `radioactive fallout`
    Found on http://wordnet.princeton.edu/perl/webwn?
    
    
11. 
    radioactive
    (ra″de-o-ak´tiv) characterized by radioactivity.
    Found on http://www.mercksource.com/pp/us/cns/cns
    
    
12. 
    radioactive
    Possessing radioactivity. Syn: radio- 2
    Found on