Emily Dickinson Lexicon

THE'SIS, n. [L. thesis; Gr. θεσις, a position, from τιθημι, to set.]

1. A position or proposition which a person advances and offers to maintain, or which is actually maintained by argument; a theme; a subject.
2. In logic, every proposition may be divided into thesis and hypothesis. Thesis contains the thing affirmed or denied, and hypothesis the conditions of the affirmation or negation. Cyc.
3. In music, the unaccented part of the measure, which the Greeks expressed by the downward beat.