The word meridian describes a gigantic imaginary circle that runs north and south on the earth's surface, from the North Pole to the South Pole. If you stood on the meridian at the North Pole, you would be at the earth's northernmost point.

Meridian can also refer to the highest stage of development. The meridian of your chess career may have been when you took out the champ from a rival school. Used as an adjective, meridian can describe something that's at the best stage of development. Your favorite skater was at his meridian form when he won the Olympic gold medal. Meridian can also describe something that takes place at noon, like your meridian boat voyage that launched precisely at noon.

Definitions of meridian
  1. noun
    an imaginary great circle on the surface of the earth passing through the north and south poles at right angles to the equator
    “all points on the same meridian have the same longitude”
    synonyms: line of longitude
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    International Date Line
    an imaginary line on the surface of the earth following (approximately) the 180th meridian
    observer's meridian
    a meridian that passes through the observer's zenith
    prime meridian
    meridian at zero degree longitude from which east and west are reckoned (usually the Greenwich longitude in England)
    magnetic meridian
    an imaginary line passing through both magnetic poles of the Earth
    type of:
    great circle
    a circular line on the surface of a sphere formed by intersecting it with a plane passing through the center
  2. noun
    the highest level or degree attainable; the highest stage of development
    synonyms: acme, elevation, height, peak, pinnacle, summit, superlative, tiptop, top, zenith
    see moresee less
    type of:
    degree, level, point, stage
    a specific identifiable position in a continuum or series or especially in a process
  3. adjective
    being at the best stage of development
    synonyms: prime
    having reached full natural growth or development
  4. adjective
    of or happening at noon
    meridian hour”
Word Family

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