There is a profusion of rebusses on the groining of the ceiling, in conformity with the taste of the age.[…]For, looking up to the groining round the centre orbs, one representing the Almighty, the other the Blessed Virgin, we find the following characters and rebusses: the letter T, the syllable Hun, the figure of a ton, for Thomas Hunton, and the figure[…] for prior.

In pachydermic idiocy the symptoms are more decided and the appearance more distinctive. In the cretin the hands are of a more normal shape, whereas in the pachydermic idiot the fingers are lumpy and the hands swollen.

IIRC from the director's commentary the name was chosen to add a bit of humility to the mission, lest the helionauts get too cocky about their cutting edge technology.

... if we would not have our bureaucracy degenerate into a pedantocracy, this body must not engross all the occupations which form and cultivate the faculties required for the government of mankind.