Laugh \Laugh\, v. i. [imp. & p. p. Laughed; p. pr. & vb. n. Laughing.]

[OE. laughen, laghen, lauhen, AS. hlehhan, hlihhan, hlyhhan, hliehhan; akin to OS. hlahan, D. & G. lachen, OHG. hlahhan, lahhan, lahh?n, Icel. hl[ae]ja. Dan. lee, Sw. le, Goth. hlahjan; perh. of imitative origin.]

1. To show mirth, satisfaction, or derision, by peculiar movement of the muscles of the face, particularly of the mouth, causing a lighting up of the face and eyes, and usually accompanied by the emission of explosive or chuckling sounds from the chest and throat; to indulge in laughter.

Queen Hecuba laughed that her eyes ran o'er. --Shak.

He laugheth that winneth. --Heywood's Prov.

2. Fig.: To be or appear gay, cheerful, pleasant, mirthful, lively, or brilliant; to sparkle; to sport.

Then laughs the childish year, with flowerets crowned. --Dryden.

In Folly's cup still laughs the bubble Joy. --Pope.

To laugh at, to make an object of laughter or ridicule; to make fun of; to deride.

No wit to flatter left of all his store, No fool to laugh at, which he valued more. --Pope.

To laugh in the sleeve

Source: Webster's Revised Unabridged Dictionary (1913)
 

Laugh \Laugh\, v. t.

1. To affect or influence by means of laughter or ridicule.

Will you laugh me asleep, for I am very heavy? --Shak.

I shall laugh myself to death. --Shak.

2. To express by, or utter with, laughter; -- with out.

From his deep chest laughs out a loud applause. --Shak.

To laugh away.
   (a) To drive away by laughter; as, to laugh away regret.
   (b) To waste in hilarity. ``Pompey doth this day laugh away his fortune.'' --Shak.

To laugh down.
   (a) To cause to cease or desist by laughter; as, to laugh down a speaker.
   (b) To cause to be given up on account of ridicule; as, to laugh down a reform.

To laugh one out of, to cause one by laughter or ridicule to abandon or give up; as, to laugh one out of a plan or purpose.

To laugh to scorn, to deride; to treat with mockery, contempt, and scorn; to despise.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Laugh \Laugh\, n. An expression of mirth peculiar to the human species; the sound heard in laughing; laughter. See Laugh, v. i.

And the loud laugh that spoke the vacant mind. --Goldsmith.

That man is a bad man who has not within him the power of a hearty laugh. --F. W. Robertson.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Sardonic \Sar*don"ic\, a. [F. sardonique, L. sardonius, Gr. ?, ?, perhaps fr. ? to grin like a dog, or from a certain plant of Sardinia, Gr. ?, which was said to screw up the face of the eater.]

Forced; unnatural; insincere; hence, derisive, mocking, malignant, or bitterly sarcastic; -- applied only to a laugh, smile, or some facial semblance of gayety.

Where strained, sardonic smiles are glozing still, And grief is forced to laugh against her will. --Sir H. Wotton.

The scornful, ferocious, sardonic grin of a bloody ruffian. --Burke.

Sardonic grin or laugh, an old medical term for a spasmodic affection of the muscles of the face, giving it an appearance of laughter.

Source: Webster's Revised Unabridged Dictionary (1913)