Low temperature, and then the rest
In current English, cold is first of all a temperature word. Air, water, metal, and weather can be cold; a person can feel cold. The same adjective also names an emotional climate: a distant look, an unwelcoming reception, a fact presented without warmth. As a noun it covers both the physical condition of low heat and the familiar viral illness that congests the nose and throat. None of those uses is a late slang overlay. The emotional sense is already Old English. The illness sense is later, and it grew out of an older habit of blaming a stuffed head on exposure rather than on a virus.
An Anglian inheritance
The origin of the word cold is a native story, not a borrowing from French or Latin. The modern spelling and vowel go back to Middle English cold, itself from the Anglian Old English form cald. West Saxon, the written standard of much of late Old English, had ċeald, with a palatal onset. That southern form did not vanish overnight: early Middle English still shows cheald, cheld, and chald in the south, roughly into the fourteenth century. Standard English followed the midland line from Anglian cald. Northern speech kept a related vowel, visible today in Scots cauld and in some northern English pronunciations.
First known use sits before the twelfth century, which is another way of saying the word is already in Old English. The noun is likewise old. It was formed inside English by converting the adjective, or from the same Germanic base; Old English already used it for lack of heat and for the bodily sensation of being chilled. Other West Germanic languages more often used a related derived noun of the type behind German Kälte, rather than the bare adjective used as a noun. English went the shorter route and still does.
A past participle that stuck
Behind Old English cald and ċeald stands Proto-West Germanic *kald, from Proto-Germanic *kaldaz. That adjective is not a simple underived root word. It is a verbal adjective, historically a past-participle type, built on the verb *kalaną, to be cold or to freeze. Old English still had the verb calan; Old Norse had kala. The dental suffix on *kaldaz is the Germanic counterpart of the participial ending seen in Latin -tus and Greek -tos. The form meant, in effect, something that had been made cold or that was in a frozen state, and then it became the ordinary word for the quality itself.
Germanic *k- here is the expected outcome of an Indo-European voiced stop after Grimm’s law. Comparative dictionaries reconstruct a Proto-Indo-European root *gel- or *ǵel-, to be cold or to freeze, often via an o-grade *gol-tó-s. Exact notation varies, but treatments agree on the participial analysis and on the verb *kalaną. The choice between a plain velar and a palatovelar depends in part on whether Balto-Slavic matches are accepted. That is a specialist disagreement, not a reason to invent a neater tree.
Latin supplies the clearest non-Germanic relatives: gelū or gelus for frost, gelāre to freeze, gelidus icy. English later borrowed several of those descendants — gelid, gelatine, congeal — so the family sits in the language twice: once native, once as learned loans. Lithuanian gelumà, severe cold or frost, is often cited as a Balto-Slavic match. Slavic words such as Russian холод are less secure; the consonants do not line up cleanly. Latin glaciēs, ice, has long been grouped with gelū, but the phonology is awkward, and some etymologists leave ice unresolved.
Cognates inside Germanic are straightforward and still recognizable: German kalt, Dutch koud, West Frisian kâld, Gothic kalds, Old Norse kaldr, and the modern Scandinavian set (Icelandic kaldur, Danish kold, Swedish kall). The English word is one member of that cluster, not an isolated coinage.
From weather to death, hunting, and a stuffed nose
The physical sense is the oldest. Late Old English already used the adjective for a person unmoved by strong feeling, so the metaphor of emotional frost is not a Victorian invention. By the mid-thirteenth century sources record the everyday relative sense: not heated, of low temperature compared with what might have been warmed. By the mid-fourteenth, cold could mean dead, the body having lost its warmth. That last sense still surfaces in phrases where someone is knocked out cold or left lying cold.
Hunting language added another layer in the 1590s: a scent or trail that only weakly affects the nose is cold. Children’s seeking games took that usage further in the nineteenth century, by the 1860s: a searcher is cold when far from the hidden object. Sales English later reused the same idea of no prior warmth of acquaintance. The noun cold call is recorded by 1953; the verb follows about a decade later.
The illness called a cold is a different kind of transfer. In the early fourteenth century the noun could mean a sickness blamed on too much exposure to low temperature, and later the chills of intermittent fever. The specific sense of a stuffed nose and throat is later, from the 1530s, named because the symptoms feel like those of being chilled. The folk theory and the viral fact are not the same thing, but the name stuck.
Compounds keep the same pattern. Cold sweat is in use by the 1630s; cold comfort, little cheer dressed as consolation, by the 1650s. To throw cold water on a plan, in the sense of discourage it, is recorded by 1808. To be left out in the cold dates from 1861; the meteorological cold front from 1921. Eighteenth-century cold cream translates an older Latin name for a cooling ointment; the cold in that name belongs to humoral medicine, not to a jar stored on ice.
Three native words, one root
A useful last detail is that English did not need Latin to talk about degrees of low heat. Chill continues Old English ċiele or ċele, a noun from the same Germanic verb family, reconstructed as *kaliz. Cool continues Old English col, a related formation from the same Indo-European root, usually a step milder than cold. Three native words, one root: a scale of sensation that was already in the language before the Norman Conquest, and a participial adjective that never stopped being the unmarked word for the thing itself.