Mawson, C.O.S., ed. (1870–1938). Roget’s International Thesaurus. 1922.

Class IV. Words Relating to the Intellectual Faculties
Division (II) Communication of Ideas
Section III. Means of Communicating Ideas
3. Written Language

595. Dissertation.

   NOUN:DISSERTATION, treatise, essay; thesis, theme; tract, tractate, tractation [obs.]; discourse, memoir, disquisition, lecture, sermon, homily, pandect, digest; excursus.
  investigation (inquiry) [See Inquiry]; study (consideration) [See Thought]; discussion (reasoning) [See Reasoning]; exposition (explanation) [See Interpretation].
  COMMENTARY, commentation, review, critique, criticism, article; leader, leading article; editorial; running commentary.
  COMMENTATOR, critic, essayist, pamphleteer, publicist, reviewer, leader writer, editor, annotator.
   VERB:COMMENT, explain, interpret, criticize, illuminate; dissert [rare] -, descant -, write -, touch- upon a subject; treat of -, take up -, ventilate -, discuss -, deal with -, go into -, canvass -, handle -, do justice to- a subject; show the true inwardness of.
   ADJECTIVE:DISQUISITIONAL, disquisitive, disquisitionary [rare]; expository, commentarial, commentatorial, critical.
  DISCURSIVE, discoursive, digressive, desultory.