Synonyms for Encephalogram (same or very similar meaning)
WordNet sense 1 (a graphical record of electrical activity of the brain; produced by an electroencephalograph):
electroencephalogram, EEG
WordNet sense 2 (an X ray of the brain made by replacing spinal fluid with a gas (usually oxygen) to improve contrast):
pneumoencephalogram
From the ODE community, based on WordNet
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