Ph.D.

Etymology
, an

Noun

 * 1) Doctor of Philosophy, a terminal research degree, the highest of academic degrees conferred by a college or university.
 * 2)  A person who holds a Ph.D. degree.
 * 1)  A person who holds a Ph.D. degree.
 * 1)  A person who holds a Ph.D. degree.

Usage notes

 * Not to be used generically to refer to all doctoral degrees. There are many other doctoral designations.