/ ˈθiːsɪs; NAmE / noun ( pl. theses / ˈθiːsiːz; NAmE /)
1.
thesis (on sth) a long piece of writing completed by a student as part of a university degree, based on their own research
2.
a statement or an opinion that is discussed in a logical way and presented with evidence in order to prove that it is true :
These latest findings support the thesis that sexuality is determined by nature rather than choice.
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WORD ORIGIN
late Middle English (originally referring to an unstressed syllable in Greek or Latin verse): via late Latin from Greek , literally placing, a proposition , from the root of tithenai to place.