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Astrology wiki

Explore wiki concepts, word origins, evidence and their connections to traditions and tools.

Meaning, evidence and context

Concepts A–Z

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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Subject

6 terms

C
Maya & Mesoamerican calendars

Calendar Round →

The combination of the 260-day and 365-day counts, repeating after 18,980 days, approximately 52 years.

Word origin, evidence & sources
Word origin · etymology
Descriptive English scholarly label.

Round refers to the recurring combined cycle of the Haab and sacred count; it is an English explanatory name for their interlocking recurrence.

How we know · epistemology
Combined-cycle arithmetic

The two counts realign after their least common multiple of 18,980 days. A Calendar Round label repeats, so it cannot uniquely identify a historical date without additional chronological information.

Maya & Mesoamerican calendars

Chol Q’ij →

Also: Chol Q'ij

The K’iche’ name for the living sacred day count, whose cultural practice should not be reduced to a generic birthday label.

Word origin, evidence & sources
Word origin · etymology
K’iche’ Maya calendrical name.

Chol Q’ij is the K’iche’ name for the sacred day count, alongside the Yucatec name Tzolk’in. These are distinct language forms, not English acronyms.

How we know · epistemology
Living cultural calendar practice

The sacred count is sustained through K'iche' knowledge and practice, beyond its arithmetic pattern. A software conversion can identify a date under stated conventions; it cannot confer the authority or lived knowledge of a daykeeper.

G
Maya & Mesoamerican calendars

GMT correlation →

Also: GMT 584283

The Goodman–Martínez–Thompson alignment of Maya and Julian day counts; this engine uses the constant 584283.

Word origin, evidence & sources
Word origin · etymology
Initialism of three researchers' surnames.

GMT stands for Goodman–Martínez–Thompson: Joseph Goodman, Juan Martínez-Hernández, and J. Eric S. Thompson. Here it does not mean Greenwich Mean Time.

How we know · epistemology
Chronological alignment convention

A correlation constant links the Long Count to Julian day numbering. This implementation declares 584283; differing correlation choices shift converted dates, so agreement on the count alone is insufficient when comparing historical chronologies.

H
Maya & Mesoamerican calendars

Haab →

Also: Haab’

A 365-day Maya calendar with eighteen twenty-day months plus a five-day period.

Word origin, evidence & sources
Word origin · etymology
Yucatec Maya calendrical name.

Haab, also written Haab’, names the solar-year calendar. Its language form is retained rather than replaced by the English calendar label.

How we know · epistemology
Historical solar-year count

The month structure defines a 365-day sequence that can be converted using a chosen correlation. Its year is not identical to the tropical year, so seasonal alignment cannot be assumed constant merely from the label solar calendar.

L
Maya & Mesoamerican calendars

Long Count →

A Maya system counting days through units including k’in, uinal, tun, katun and baktun; correlation links it to other calendars.

Word origin, evidence & sources
Word origin · etymology
Descriptive English scholarly label.

Long distinguishes a continuing count of elapsed days from shorter repeating calendar cycles; count names its chronological tally.

How we know · epistemology
Historical day-count notation

The units record elapsed days from an epoch rather than a recurring birthday category. Converting to another calendar requires a stated correlation; interpretation of an inscription also needs its historical and linguistic context.

T
Maya & Mesoamerican calendars

Tzolk’in →

Also: Tzolkin · Tzolk'in

A 260-day Maya count combining thirteen numbers with twenty day names; names and living practices vary by language and community.

Word origin, evidence & sources
Word origin · etymology
Yucatec Maya calendar name in modern spelling.

Tzolk’in is the Yucatec name used for the 260-day calendar. The apostrophe marks a glottalized consonant; no first coiner is established here.

How we know · epistemology
Historical and living calendar count

The thirteen-number and twenty-name cycles make the day sequence reproducible once an anchor is fixed. A converted date alone does not reproduce the community-specific language, ritual authority or interpretive practice associated with the count.