A native word for a basic fact
In current English, shit is a vulgar term for feces and for the act of defecating. It also covers a wide slang range: stuff, nonsense, trouble, a contemptible person, and a sharp interjection of anger or dismay. Those extra senses feel contemporary. The bodily meaning is not. English has had a Germanic word of this shape for as long as the language has been written.
How it reached English
The origin of the word shit is native inheritance, not a later loan from French or Latin. The noun is already Old English. The form scitte meant diarrhea or a purging of the bowels, not dung in the most general sense. A mid-tenth-century medical compilation known as Bald's Leechbook uses it that way: food that fails to digest and turns to a harmful liquid and diarrhea. The Oxford English Dictionary therefore places the noun in the Old English period, before 1150. A related noun reconstructed as scite, dung, is recovered mainly from place-names rather than from continuous prose. Modern dictionaries disagree on whether today's noun continues that Old English item or was rebuilt from the verb. The Germanic stock is not in dispute.
The verb is shakier in the written record. Comparative Germanic evidence, and Old English compounds such as besciten, soiled with excrement, point to a strong class-I verb reconstructed as scitan, to defecate, with a long vowel in the infinitive. The simplex infinitive itself is not securely attested in the surviving Old English corpus. Some popular etymologies write it as if it were on the page; specialist treatments are more careful. The first clear written verb is Middle English, around 1335, in a satirical poem from the Kildare manuscript that mocks tanners and their reeking vats. Middle English spellings include shiten, schiten, and shyte. Dictionary.com dates the family as a whole before 900, counting the noun; the Oxford English Dictionary dates the verb to the Middle English period, with earliest evidence near 1335. Both can be true at once.
The older root, and why the vowel shortened
The historical English verb had a long vowel. That length is still audible in the British and Irish variant shite. The short-i form shit is the usual modern spelling. The shortening is generally credited to the noun or to the past participle of the strong verb, which already had a short vowel in the inherited pattern: long vowel in the infinitive, short vowel in the past plural and participle. The playful past tense shat, modeled on sit and sat, is not the old past. It is recorded from the eighteenth century as a humorous analogical form.
Behind Old English stand Proto-West Germanic skitan and Proto-Germanic skitaną. Close relatives are easy to name: Dutch schijten and schijt, German scheissen and Scheisse, Old Norse skita, Swedish skita, Danish skide, Icelandic skita, and Frisian verbs such as North Frisian skitj. English also has skite, which arrived by a more northerly, Norse-related path and later went its own way.
Many handbooks take the Germanic verb further back to a Proto-Indo-European root meaning to cut, split, or separate. The proposed image is of matter leaving the body, a pattern also visible in Latin excrementum, built on a verb of separating out. On that reconstruction the English word is a distant cousin of science and conscience, which rest on Latin scire, to know, itself linked to distinguishing one thing from another. The step is not unanimous. Vladimir Orel and the American Heritage root appendix accept it; Guus Kroonen's dictionary of Proto-Germanic is cautious. Lithuanian sikti, to defecate, is sometimes offered as a Baltic match, but that comparison stands or falls with the same deeper etymology. Where specialists disagree, the Germanic layer is the solid ground.
From a medical noun to a print taboo
In the oldest readable English, the noun is specific: diarrhea, not a general word for solid waste. Middle English still uses it in that medical sense. Fourteenth-century prose more often reached for turd or filth when it needed a everyday noun for dung, and other native forms such as scytel and shitel were available. The broader sense of excrement is dated to the late sixteenth century.
From about 1600 the word was strongly taboo in print. It does not appear in Shakespeare or in the King James Bible. Even coarse eighteenth-century publications often hid it behind dashes. Censors still fought it well into the twentieth century: Joyce's Ulysses and Cummings's The Enormous Room in 1922, a Hemingway story in the Atlantic Monthly in 1957, and some American dictionaries as late as 1970. Speech did not wait on typesetters.
Meanings spread from the body to social contempt and then to almost anything unpleasant. Calling a person shit is recorded by the early sixteenth century, around 1508. Using the verb for disrespect appears in the early 1900s; using it to mean lie or tease is from the 1930s. Misfortune as shit is twentieth-century slang. As a standalone curse, print evidence is later than folk memory would suggest. The Oxford English Dictionary's interjection is dated 1865; a diary from 1844 already uses it as a one-word outburst. Dates that put the printed exclamation near 1920 are therefore too late for the spoken pattern, even if mass-circulation examples cluster later.
A durable false story claims the letters stand for ship high in transit, supposedly a cargo instruction for manure. That is a joke, not a history. The word is centuries older than such acronyms, and it was never coined in a shipping office.
A clinical sense that outlived the clinic
The useful fact is small. In the earliest English we can actually read, the noun named a purge, not feces in general. The four-letter word that now means almost anything unpleasant is, in writing, a later widening of a medical term that physicians already had, sitting on a Germanic verb whose infinitive barely made it onto the page.