What English uses the word for
In present-day English, a king is first of all a male monarch: the man who heads a kingdom, whether his power is absolute, limited by law, or mostly ceremonial. The same noun stretches easily. It names the person who stands first in some field, the chess piece whose capture ends the game, the high face card marked K, and a draughts piece that has been crowned. All of those uses rest on one inherited Germanic word, not on a later borrowing from Latin or French.
The origin of the word king is therefore a story about kin, belonging, and how a title for a tribal leader grew into the name of a European office.
Native, not borrowed
English did not import this noun. It inherited it. The immediate ancestor is Old English cyning, already a word for a ruler and already used as a title. Alongside the full form, late Old English also had shorter spellings such as cyng and cing. Those reduced shapes are the ones that settle, through Middle English king, kyng, and kynge, into the modern spelling.
The Old English word itself continues Proto-West Germanic kuning and, behind that, Proto-Germanic kuningaz (a parallel reconstruction kunungaz is sometimes given for the North Germanic type). Cognates fill the family: Dutch koning, German König, West Frisian kening, Old Norse konungr, Swedish kung and konung, Danish konge. The match is so regular that the word is treated as Common Germanic.
Gothic is the notable gap. The East Germanic record does not show kuningaz. Gothic used þiudans, built on a word for a people or nation, and Old English had a related title þeoden. So the king type is general in the North and West, but it was not the only old Germanic way to name a ruler.
First English use belongs to the Old English period, well before 1150. In that language the word covered chiefs of Anglian and Saxon tribes, the heads of the kingdoms those groups founded, and the British and Danish leaders they fought. It was already a political title, not a later scholarly coinage.
Kin plus a suffix
The morphology is unusually clear for a word this old. Proto-Germanic kuningaz is widely analysed as kunją, meaning clan, family, or kin, plus -ingaz, a suffix of belonging or descent. English still has the first half as kin, from Old English cynn. The second half is the same -ing that marks affiliation in names and group words. In that analysis, a king is etymologically someone of the kin, or a descendant of a kin.
The deeper root of kunją is Proto-Indo-European ǵenh₁-, a verb of begetting and producing. That is the same stock that yields Latin genus and Greek genos, and it is why dictionaries can point from king to the same Indo-European folder that holds kin and kind. American Heritage, for example, sends the Old English form to that root. The connection is linguistic, not a claim that every later king was chosen for blood alone.
What remains uncertain is the original social sense, not the family of forms. One reading makes the word a leader of a people: the man at the head of a kinship group. Another makes it a person of noble or even sacred descent: someone who belongs to a royal stock, possibly one that traced itself to the gods. Anglo-Saxon succession, which drew the next ruler from a royal cynn, fits the genealogical picture. So does the old contrast, already noted by Roman writers on the Germans, between kings chosen for birth and war-leaders chosen for prowess. Etymologists still disagree which idea the suffix first carried. The link to kin is not seriously in doubt; the exact notion is.
How the meaning widened
In early England the title was not reserved for a single sovereign of a modern nation. Several tribal kings could exist at once. As Wessex rose in the ninth and tenth centuries, the West Saxon ruler became king of a larger English people, and many of those smaller kingships ended. The word itself grew more imposing as European states took shape. Later still, English speakers used it for rulers of very different scale: emperors and city-kings of the ancient Mediterranean in historical writing, and local chiefs elsewhere, often through colonial naming rather than through any native title that matched cyning.
A figurative sense, a person who dominates a class or craft, is recorded from the late fourteenth century. From there it is a short step to oil kings, chess kings, and the casual modern use of king for a man treated with respect. None of that overwrites the older political meaning; it borrows the ranking.
Game vocabulary is later and more dated. The chess piece is so called from about 1400. The playing card follows in the 1560s. Draughts and checkers use the word from 1820, when a piece that reaches the far rank is crowned. The biblical Magi appear as the Three Kings from around 1200. Each of these is a transferred title, not a separate etymology.
French did leave a rival on the edge of English. Middle English had roy, from Old French roi, but it never displaced the native noun. King stayed the ordinary word; royal and royalty took the Latin-French route into the same semantic field.
A frozen loan as a dating clue
Because Finnic and Slavic languages borrowed the Germanic word early, they preserve shapes English itself has worn down. Finnish kuningas still looks close to kuningaz, complete with a final syllable English lost centuries ago. Old Church Slavonic kunegu and Russian knyaz (a prince or duke) come from the same Germanic source, as does Lithuanian kunigas, which shifted toward clergyman. Those loans do not prove how Anglo-Saxon kingship worked. They do show that the Germanic title was already important enough, in late antiquity or the early Middle Ages, to travel outside the Germanic-speaking world.
The compact modern English form hides that older length. King looks like a short native monosyllable. Its history is a longer word about belonging to a kin, shortened in Old English, kept through Middle English, and only later stretched across chessboards, card decks, and metaphors of rank.