noun pl. theses -·ses′ (-sēz′)

1. 1. in classical Greek poetry, the long syllable of a foot
   2. in later poetry, the short or unaccented syllable or syllables of a foot
2. a proposition maintained or defended in argument, formerly one publicly disputed by a candidate for a degree in a medieval university
3. a formal and lengthy research paper, esp. a work of original research written in partial fulfillment of the requirements for a master's degree
4. an unproved statement assumed as a premise
5. in Hegelian philosophy, the initial, least adequate phase of development in dialectic

Etymology: L < Gr, a placing, position, proposition < base of tithenai, to put, place: see do