Dictionary term
International Atomic Time
Direct answer
International Atomic Time: International Atomic Time, or TAI, is a continuous atomic time scale computed by the BIPM from clocks maintained by timing laboratories worldwide.
TAI is the international continuous atomic time scale maintained from an ensemble of clocks.
TAI is the international continuous atomic time scale maintained from an ensemble of clocks.
A cycle or timeline schematic for comparing the named timekeeping concept.Quick reference
- Use when
- Use International Atomic Time when explaining atomic continuity, leap-second offsets, and relationships among modern time scales.
- Do not use it for
- Do not call TAI a civil time zone; it has no daylight-saving or local-date rules.
- Reference category
- Calendars & Timekeeping
- Related terms
- Terrestrial Time, UT1, Calendar, Julian Date
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The story behind International Atomic Time
International clock comparisons and atomic standards enabled TAI to replace astronomical rotation as the most stable duration reference.
International Atomic Time in spiritual tradition
Spiritually, TAI reflects international cooperation in preserving a common measure of duration.
International Atomic Time: fact and faith, kept distinct
This is a factual calendar, astronomy, Earth-science, cultural-history, or observational reference. It can support wonder and practical planning without becoming a claim of fate, spiritual causation, or private revelation.
International Atomic Time in numerology
International Atomic Time is not a numerology claim. Any numbers attached to it should retain their ordinary scientific, calendrical, navigational, or historical meaning unless a separate symbolic interpretation is clearly labeled.
Why International Atomic Time matters
TAI provides a stable SI-second foundation for UTC, TT, navigation, telecommunications, and precision science.
International Atomic Time at work: an example
UTC differs from TAI by an integer number of accumulated leap seconds.
Where interpretation stops
International Atomic Time is presented as sourced astronomy, calendrical, Earth-science, cultural, or instrument-history reference. Definitions should distinguish measured phenomena from civil convention and historical interpretation, preserve location and time dependencies, and avoid turning factual sky data into a deterministic personal claim.
Sources and editorial method
Research references used for this entry include:
- BIPM SI Brochure Annex: Time - International metrology reference for the SI second, TAI, UTC, and Terrestrial Time.
- NIST: UTC(NIST) Time Scale - Official description of UTC realization, atomic time, and leap-second coordination.
- Source
- The Great Almanac Dictionary
- Category
- Calendars & Timekeeping
- Also appears in
- Calendars & Timekeeping
- Aliases
- None listed
- Last updated
- 2026-07-16
Trace atomic and civil time
International Atomic Time in a book is one thing; International Atomic Time in your own birth chart is your life. The Oracle casts your real chart and tells you what it means for your love, your work, and your year ahead, in conversation, free.
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More in Calendars & Timekeeping
- Local Mean Solar Time
- Ordinal Date
- Sidereal Year
- Unix Time
- Astronomical Year Numbering
- Civil Calendar
- Draconic Year
- Golden Number
Common questions
What is International Atomic Time?
International Atomic Time, or TAI, is a continuous atomic time scale computed by the BIPM from clocks maintained by timing laboratories worldwide.
How is International Atomic Time used in an almanac?
Use International Atomic Time when explaining atomic continuity, leap-second offsets, and relationships among modern time scales.
What should I avoid when interpreting International Atomic Time?
Do not call TAI a civil time zone; it has no daylight-saving or local-date rules.
