ABD meaning in Academic & Science ?

"All but dissertation" (ABD) is a term identifying a stage in the process of obtaining a research doctorate in the United States and other countries. In typical usage of the term, the ABD graduate student has completed the required preparatory coursework, passed any required preliminary, comprehensive, doctoral qualifying examinations, and met all other requirements except for the research requirements, typically including the writing and defense of a dissertation. The informal ABD designation also indicates that someone is no longer simply a doctoral student, but rather has formally upgraded their status to a doctoral candidate and has entered the most advanced phase of their research and dissertation development.

A student attaining this level also may be granted a formal Candidate in Philosophy degree or status at a few institutions. Some universities, including Columbia, Yale, and George Washington, may award a formal Master of Philosophy (MPhil) degree for these achievements.

The use of ABD or the similar PhD(c) for PhD candidate (also PhD-c or PhDc) as a credential has been criticized as potentially misleading by some writers as the terms are not widely understood outside of academia or indeed outside of the US.