'Thesis' vs 'dissertation'



Are the words (thesis and dissertation) used interchangeably in English, or is there a different between these terms? Is it possible to use Master´s thesis and PhD thesis?

Posted 01 August 2002
There is a difference between the terms. A student seeking his/her master's degree works on a thesis; one seeking a Ph.D. works on a dissertation.

The Random House Dictionary of the English Language (Random House, 1966) has this under its entry for "thesis": "a dissertation on a particular subject in which one has done original research, as one presented by a candidate for a diploma or a degree, especially a master's degree."

The same dictionary has this under its entry for "dissertation": "A written essay, treatise or thesis, especially one written by a candidate for the degree of Doctor of Philosophy."

It is interesting to note that both entries also contain more generalized definitions, such as "any formal discourse in speech or writing,"without mentioning either the master's degree or the Ph.D. degree. Some smaller dictionaries, too, have overlapping definitions without mentioning either degree. However, in usage referring to academic pursuits today, there is the distinction between "thesis" - which is the what a master's degree candidate seeks - and "dissertation" - which is what the Ph.D. candidate seeks.