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 I. Nature of Ideas Communicated

518. Intelligibility.

   NOUN:INTELLIGIBILITY; clearness, clarity, explicitness &c. adj.; lucidity, comprehensibility, perspicuity; legibility, plain speaking (manifestation) [See Manifestation]; precision [See Truth]; phonanta sunetoisi [Gr. φωναντα σϵνετoισι], a word to the wise.
   VERB:BE INTELLIGIBLE &c. adj.; speak for itself, speak volumes; tell its own tale, lie on the surface.
  RENDER INTELLIGIBLE &c. adj.; popularize, simplify, clear up; elucidate (explain) [See Interpretation].
  UNDERSTAND, comprehend; take, – in; catch, grasp, follow, collect, master, make out; see with half an eye, see daylight, see one’s way [all colloq.]; enter into the ideas of; come to an understanding.
   ADJECTIVE:INTELLIGIBLE; clear, clear as -day, – noonday, – crystal; lucid; perspicuous, transpicuous; luminous, transparent.
  easily understood, easy to understand, for the million, intelligible to the meanest capacity, popularized.
  PLAIN, distinct, clear-cut, hard-hitting, to the point, explicit; positive; definite (precise) [See Truth].
  unambiguous, unequivocal, unmistakable (manifest) [See Manifestation], unconfused; legible, recognizable; obvious [See Manifestation].
  GRAPHIC, telling, vivid; expressive (meaning) [See Meaning]; illustrative (explanatory) [See Interpretation].
   ADVERB:in plain -terms, – words, – English; hitting the nail on the head.
  1. He that runs may read (manifest) [See Manifestation].
  2. That wayfaring men, though fools, should not err therein.—Bible