Definition of theses:
(n) :
(by extension) A lengthy essay written to establish the validity of a thesis (sense 1.1), especially one submitted in order to complete the requirements for a non-doctoral degree in the US and a doctoral degree in the UK; a dissertation.
(n) :
(rhetoric) A proposition or statement supported by arguments.
(n) :
Senses relating to logic, rhetoric, etc.
(n) :
(logic) An affirmation, or distinction from a supposition or hypothesis.
(n) :
(philosophy) In the dialectical method of Georg Wilhelm Friedrich Hegel: the initial stage of reasoning where a formal statement of a point is developed; this is followed by antithesis and synthesis.
(n) :
(mathematics, computer science) A conjecture, especially one too vague to be formally stated or verified but useful as a working convention.