thesis

(rhetoric) A proposition or statement supported by arguments.

(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.

(mathematics, computer science) A conjecture, especially one too vague to be formally stated or verified but useful as a working convention.

(logic) An affirmation, or distinction from a supposition or hypothesis.

(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.

(music, prosody, originally) The action of lowering the hand or bringing down the foot when indicating a rhythm; hence, an accented part of a measure of music or verse indicated by this action; an ictus, a stress.

(music, prosody, with a reversal of meaning) A depression of the voice when pronouncing a syllables of a word; hence, the unstressed part of the metrical foot of a verse upon which such a depression falls, or an unaccented musical note.