/ˌsɪŋkrəˈnɪsɪti/
[noun] A meaningful coincidence where two or more events happen at the same time in a way that seems connected, even though there is no obvious cause linking them. The word is most often used to describe moments that feel too significant to be purely accidental.
Carl Jung invented this word to describe coincidences so meaningful they seemed to break the laws of cause and effect.
The story of synchronicity begins in ancient Greece, with the word 'chronos' (χρόνος), meaning time. The Greeks also had the prefix 'syn-' (σύν), meaning together or with. Combining these gave the adjective 'synchronos' (σύγχρονος), meaning happening at the same time. This root travelled into Latin as 'synchronus', then into scientific English in the 17th century as 'synchronous', meaning occurring simultaneously. From 'synchronous' came 'synchronize' in the 18th century, meaning to make things happen at the same time, and then 'synchronism' as a noun describing the state of being in time together.
The specific word 'synchronicity', however, is a 20th-century invention, and it has a single, identifiable creator: the Swiss psychiatrist Carl Gustav Jung. Jung spent decades noticing that his patients often experienced striking coincidences — a person dreaming of a golden scarab beetle the same night a real scarab flew into the therapy room, for example. These events seemed too meaningful to be random, yet no physical cause connected them. Jung needed a word for this phenomenon, and he built one from the Greek roots already embedded in scientific vocabulary.
Jung introduced the concept publicly in a foreword he wrote in 1930, then developed it fully in his 1952 essay 'Synchronizität als ein Prinzip akausaler Zusammenhänge', published in German and translated into English as 'Synchronicity: An Acausal Connecting Principle'. The word he coined — 'Synchronizität' in German, directly becoming 'synchronicity' in English — moved from Greek 'chronos' through the Latin 'synchronus' and the scientific English 'synchronous' before Jung added the suffix '-icity' to create an abstract noun naming not just the state of being simultaneous, but the mysterious quality of meaningful simultaneousness.
What makes the word genuinely surprising is how it deliberately challenges scientific thinking from within scientific language. Jung was a trained doctor using proper Greek and Latin roots — the respectable building blocks of medical terminology — to name something that defied the central scientific principle of cause and effect. He was not saying coincidences were magical. He was saying that the universe might contain a second kind of connection beyond causality: one based on meaning rather than mechanics. The word itself performs this tension, sounding rigorously scientific while pointing toward something almost mystical.
After Jung, 'synchronicity' escaped its clinical origins and entered popular culture with remarkable speed. The 1983 album 'Synchronicity' by The Police, which contained the global hit 'Every Breath You Take', introduced the word to millions who had never read Jung. By the late 20th century, the word was used loosely to describe any coincidence that felt personally significant — running into an old friend on the day you were thinking about them, or opening a book to the exact page that answers your question. The precision Jung intended softened into everyday wonder, but the word retained its philosophical warmth: the sense that the universe might occasionally arrange itself around us in ways we cannot fully explain.