Today's pretentious word from Webster's Third New International Dictionary and Seven Language Dictionary, Unabridged: Volume 2, H-R is 'pharmacopolist'.
Pharmacopolist: "One who sells drugs".
Using this word will most likely land you in trouble, as if you refer to the pharmacologist as a pharmacopolist, people will think you are stupid. You will have to explain your way out of sounding dumb, but if you are trying to sound pretentious, go for it!