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512 concepts, each with a definition, word origins, a brief epistemology and source links. Hover or focus a dotted term to preview it. Tap once for the preview, then follow the entry.

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1 terms

L
Calendar conventions

Leap month →

Also: intercalary month

An additional month inserted by a calendar’s intercalation rules. Chinese and Tibetan calendars determine and label it with their own rules; an inserted month is different from a repeated Tibetan lunar day.

Word origin, evidence & sources
Word origin · etymology
Descriptive English calendar phrase; intercalary is a Latin-derived synonym.

Leap month is the English label for an inserted calendar month; its exact coinage is not established by these sources. Intercalary comes from Latin intercalarius, related to intercalare, inserting a day or month into a calendar.

How we know · epistemology
Calendar intercalation rule

An extra month follows the selected calendar’s alignment and numbering rules. In the Phugpa method implemented here the leap occurrence precedes the regular month of the same number; that ordering must not be transferred automatically to another tradition.