Absurd, a.
Etymology: [L. absurdus harsh-sounding; ab + (prob) a derivative fr. a root svar to sound; not connected with surd: cf. F. absurde. See Syringe.]
Contrary to reason or propriety; obviously and fiatly opposed to manifest truth; inconsistent with the plain dictates of common sense; logically contradictory; nonsensical; ridiculous; as, an absurd person, an absurd opinion; an absurd dream. This proffer is absurd and reasonless. Shak. 'This phrase absurd to call a villain great. Pope. p. 9
Syn. -- Foolish; irrational; ridiculous; preposterous; inconsistent; incongruous. -- Absurd, Irrational, Foolish, Preposterous. Of these terms, irrational is the weakest, denoting that which is plainly inconsistent with the dictates of sound reason; as, an irrational course of life. Foolish rises higher, and implies either a perversion of that faculty, or an absolute weakness or fatuity of mind; as, foolish enterprises. Absurd rises still higher, denoting that which is plainly opposed to received notions of propriety and truth; as, an absurd man, project, opinion, story, argument, etc. Preposterous rises still higher, and supposes an absolute inversion in the order of things; or, in plain terms, a "putting of the cart before the horse;" as, a preposterous suggestion, preposterous conduct, a preposterous regulation or law.
1 other Webster entry under this spelling
Absurd, n.
An absurdity. [Obs.] Pope.
Shades of meaning
That is absurd which is contrary to the first principles of reasoning; as, that a part should be greater than the whole is absurd. A paradoxical statement appears at first thought contradictory or absurd, while it may be really true. Anything is irrational when clearly contrary to sound reason, foolish when contrary to practical good sense, silly when petty and contemptible in its folly, erroneous when containing error that vitiates the result, unreasonable when there seems a perverse bias or an intent to go wrong. Monstrous and preposterous refer to what is overwhelmingly absurd; as, "O monstrous! eleven buckram men grown out of two," SHAKESPEARE 1 King Henry IV, act ii, sc. 4. The ridiculous or the nonsensical is worthy only to be laughed at. The lunatic's claim to be a king is ridiculous; the Mother Goose rimes are nonsensical. Compare incongruous.