[1] : The Collaborative International Dictionary of English v.0.48

magneto \magne"to\ ma^gn=e"t-o, n.
   a small electric generator with an armature rotating in a
   magnetic field, having a secondary winding that generates a
   high voltage, such as one used to generate a voltage
   sufficient to cause a spark to jump between the poles of a
   spark plug in an internal-combustion engine.
   wordnet 1.5

[2] : The Collaborative International Dictionary of English v.0.48

magneto- \mag"neto-\, pref. see magnet.
   a prefix meaning pertaining to, produced by, or in some way
   connected with, magnetism.
   1913 webster magneto-electric
see also:
magnet 

[3] : WordNet (r) 2.0

magneto
     n : a small dynamo with a secondary winding that produces a high
         voltage enabling a spark to jump between the poles of a
         spark plug in a gasoline engine syn: magnetoelectric
         machine
see also:
magnetoelectric machine 

Magneto- >> M Words
Magneto-, definition of term: Magneto-
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