noun, feminine/tɛz/plural: thèses
thesis, supposition, theory; thesis, essay, dissertation (lengthy essay written to establish the validity of a theory, especially one submitted in order to complete the requirements for a degree); thesis (the initial stage of reasoning where a formal statement of a point is developed, followed by the antithesis and the synthesis)
“une thèse de doctorat, une thèse doctorale”
Learned borrowing from Latin thesis, itself borrowed from Ancient Greek θέσις (thésis).