in stitches
informal

- if a joke or funny story has you in stitches, it makes you laugh a lot

- If you are in stitches, you cannot stop laughing

Cambridge Dictionary / Collins CoBuild

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ORIGIN

Since the 12th century, the word stitch has enjoyed several meanings. Firstly, it means a stab or prick with a sharp instrument, such as a needle or dagger. From around the same time, it was also used figuratively for a sharp pain in the side, as if caused by such a sharp instrument.

The term "stitch" originally referred to a sudden, sharp pain, particularly a sudden localized jabbing pain, such as might be caused by a needle and is now generally used of a muscle spasm in the side caused especially by exertion.

The association of stitches with laughter, however, is generally attributed to Shakespeare. In Act 3, Scene 2 of Twelfth Night, where Maria says: "If you desire the spleen, and will laugh yourselves into stitches, follow me".

Although the precise idiom dates only from about 1930, the first available reference after that dates to 1914. A review published in The Lowell Sun read: "There's a new face among the members in Ben Loring, a natural-born comedian, who seems to have no difficulty whatever in keeping his audience in stitches of laughter and glee".

The phrase nicely connects the physical sensation of painful laughter with the medical term for side pain, creating a vivid idiom that has endured for over 400 years.

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SEVEN WAYS TO LAUGH

The following words refer to making a sound of enjoyment while smiling, usually in response to something that is funny:

- LAUGH = the most common word, used in most situations to refer to making a loud sound of pleasure or joy while smiling.

- CHUCKLE = If someone laughs quietly, the verb chuckle is sometimes used.

- GIGGLE = The verb giggle is often used when someone laughs in a quiet, childish way, often at something silly or rude, or because they are nervous.

- SNIGGER (UK), SNICKER (US) = If someone laughs in a childish and unkind way, you can use the word snigger in the UK or, in snicker in the US.

- CHORTLE = Chortle can be used when someone laughs because of being pleased, especially at someone else’s bad luck. 

- CRACK UP = The phrasal verb crack up or the phrase “burst out laughing” can be used when someone suddenly starts laughing, often uncontrollably.

- IN STITCHES = If someone is laughing so much that they cannot stop, use this phrase especially in informal situations.

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SYNONYMS

be rolling in the aisles, bust a gut, cackle, chortle, chuckle, crack up, fall about the place, giggle, guffaw, gurgle, have/be in hysterics, hold one’s sides, IN STITCHES, laugh, laugh like a drain, snigger (US snicker), teehee, titter,

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SMUGGLE OWAD into an English conversation today, say something like:

“I was IN STITCHES while watching that film last night.”