Synonyms for Breathing (same or very similar meaning)
WordNet sense 1 (the bodily process of inhalation and exhalation; the process of taking in oxygen from inhaled air and releasing carbon dioxide by exhalation):
respiration, ventilation, external respiration
WordNet sense 2 (passing or able to pass air in and out of the lungs normally; sometimes used in combination):
eupneic, eupnoeic
From the ODE community, based on WordNet
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