phrenics

noun

1. (uncountable)The branch of science that relates to the mind; mental philosophy.
2. (uncountable)The phrenic nerves; the nerves that control the diaphragm.

   “One sees plainly, that while old rabbits, after removal of the influence of the phrenics, can still reach from ½ to 8/9 of the normal quantity of air used, in young animals the proportion stands so that they only respire from ¼ to 1/6 in one minute; and thus they satisfy their need of air so unsatisfactorily that they soon die.”

   “If the phrenics are both cut, the diaphragm is paralyzed; if a single one, that side only remains passive.”