Noun
(historical, in the Netherlands) A person who has passed an doctoral exam at a university, but has not yet attained a doctorate.
(uncommon) Alternative form of doctorand
Source: en.wiktionary.orgOnce a doctorate is achieved the doctorandus is promoted to doctor, and no longer uses the drs. abbreviation. Source: Internet
This abbreviation stands for the Dutch title doctorandus Latin for "he who should become a doctor" (female form is "doctoranda"). Source: Internet