Search Result for "tokamak": 
Wordnet 3.0

NOUN (1)

1. a doughnut-shaped chamber used in fusion research; a plasma is heated and confined in a magnetic bottle; 



WordNet (r) 3.0 (2006):

tokamak
    n 1: a doughnut-shaped chamber used in fusion research; a plasma
         is heated and confined in a magnetic bottle