The most common root meaning “time” is the Greek root chron, from the word chronos. It appears in dozens of everyday English words like chronological, chronic, and synchronize. But it’s not the only one. Latin, and even older language families, contributed several roots related to time, each with a slightly different shade of meaning.
Chron: The Greek Root for Time
If you’re studying word roots for a class, chron is the one you need first. It comes from the Greek chronos, meaning measurable, sequential time. English borrowed it heavily:
- Chronological: arranged in time order
- Chronicle: a record of events in the order they happened
- Chronic: lasting a long time (as in a chronic illness)
- Chronometer: a precise instrument for measuring time
- Synchronize: to make things happen at the same time
- Anachronism: something placed in the wrong time period, like a wristwatch in a medieval painting
- Chronograph: an accurate timer for recording elapsed time
Even the word crony, meaning a close friend, traces back to chron. The idea is a companion you’ve known over a long stretch of time.
Ancient Greek actually had two separate words for time. Chronos referred to quantitative, clock-and-calendar time: seconds ticking, years passing. Kairos, by contrast, meant the right or opportune moment. The concept originated in Greek archery, describing the precise instant an archer finds the perfect opening to release an arrow. Kairos was also personified as the god of opportunity. While chronos gave English far more vocabulary, kairos still appears in theology and rhetoric to describe moments of special significance rather than measured duration.
Temp: The Latin Root for Time
The Latin root temp, from tempus, also means “time” and shows up in a different set of common words:
- Temporary: lasting only a short time
- Contemporary: existing at the same time, or belonging to the present time
- Tempo: the speed or timing of something, especially in music
- Extemporaneous: done without preparation, literally “out of time” to get ready
- Temporize: to delay in order to gain more time
The famous Latin phrase tempus fugit, “time flies,” comes directly from this root. If chron tends to appear in words about measuring or recording time, temp leans more toward the quality or duration of time, whether something is brief, current, or well-timed.
Hora: The Root Behind “Hour”
The English word “hour” comes from the Greek hōra and its Latin form hora. Originally, hōra didn’t just mean a sixty-minute block. It referred to any defined segment of time set by natural patterns: a season, a time of day, or a period of the year. The ancient Romans divided daylight into twelve horae of varying length depending on the season, so a summer hour was longer than a winter hour.
In Greek mythology, the Horae were goddesses who presided over the changing seasons and kept watch at the gates of heaven. The word “horoscope” also comes from this root, literally meaning an observation of the hour (of someone’s birth). So does “horology,” the study and art of measuring time.
Ann and Enn: Roots for Yearly Time
When time is measured in years, the Latin roots ann and its variant enn take over. Both mean “year,” and they produced a large family of English words:
- Annual: happening once a year
- Anniversary: the yearly turning of a date
- Perennial: continuing through the years, recurring
- Biennial: every two years
- Millennium: a 1,000-year span
- Centennial: a 100-year mark
The phrase Anno Domini (A.D.) translates to “in the year of the Lord.” And annals, meaning a historical record, originally referred to year-by-year accounts of events.
Aev: The Root for Ages and Eons
The Latin word aevum originally meant “age,” “eon,” or “everlasting time.” It gave English a cluster of words for vast or indefinite stretches of time. “Medieval” combines medi (middle) with aev, literally “the middle age.” “Primeval” means belonging to the first age. “Longevity” contains the same root, pointing to a long span of life.
Medieval philosophers took aevum seriously as a technical concept. Thomas Aquinas and others at the University of Paris in the 13th century developed a system of five measures of duration, from ordinary time (for beings with limited existence) all the way up to the eternal, with aevum sitting in between to describe things that have a beginning but no end.
Scientific Prefixes for Deep Time
In geology and paleontology, Greek prefixes mark different eras. Paleo means ancient, meso means middle, and ceno (sometimes written caeno) means recent. These combine with other roots to name the major eras of Earth’s history: the Paleozoic (ancient animal life), Mesozoic (middle animal life), and Cenozoic (recent animal life). They aren’t roots for “time” in the strict sense, but they function as time markers in scientific vocabulary.
The Deep Origin: Proto-Indo-European
Many of these roots trace back even further. Linguists have reconstructed a Proto-Indo-European root, spoken thousands of years before Greek or Latin existed, that connects words for “year” and “time” across many language families. One key root meant “to walk” or “to wander,” reflecting the idea that time is something that moves or passes. It eventually became the Latin annus (year) and the Gothic word for year.
Another ancient root meant “turning,” and it survived into the Slavic languages as the word for time. Old Church Slavonic vrěmę (time) comes from a root meaning “a turning,” capturing the cyclical nature of seasons and years. The Greek hōra may likewise connect to an ancient root meaning “to go,” reinforcing the universal intuition that time is movement, a thing always in motion.
So while chron is the single most useful answer to “what root means time,” the full picture is richer. Greek and Latin gave us separate roots for measured time, seasonal time, yearly time, and vast stretches of time, each one shaping a different corner of our vocabulary.