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Wiki concept · Time & location

Ambiguous local time

Also called time fold

A clock reading repeated when clocks move backward; an offset or fold choice is needed to identify the instant.

In this entry

Word origin · etymology

Descriptive computing label.

Ambiguous names a wall-clock reading with more than one possible instant. Time fold is the backward-clock metaphor used in time-zone software.

Python PEP 495: Local Time Disambiguation ↗

How we know · epistemology

Time-zone conversion rule

A backward clock change can map one local reading to two instants. The clock record alone cannot choose between them; an offset, occurrence choice or additional historical evidence is needed.

IANA: time-zone database ↗

Connected concepts

Browse other concepts in Time & location →

These links connect subjects and terminology. They do not establish a shared historical origin.

Sources & provenance

Use the citations beside each section to distinguish a calculation convention, a historical teaching and an editorial example.

Find these sources across the wiki →

  1. IANA: time-zone database ↗
  2. Python PEP 495: Local Time Disambiguation ↗