an instrument or licence given by colleges, societies, &c. to a clergyman to exercise the ministerial function, or to a physician to practise the profession, &c. after passing examination, or admitting him to a degree.

in chemistry, &c. a double vessel. To boil in diplomate, is to set one vessel, containing the ingredients intended to be acted upon, in another larger vessel full of water, and to this last the fire is to be applied.