"phase function" meaning in English

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      "expansion": "phase function (plural phase functions)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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          "langcode": "en",
          "name": "Functions",
          "orig": "en:Functions",
          "parents": [
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            "Calculus",
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      "glosses": [
        "A function that describes the angular distribution of light reflected from a body when illuminated from a specific direction"
      ],
      "id": "en-phase_function-en-noun-oB2AUvTB",
      "links": [
        [
          "astronomy",
          "astronomy"
        ],
        [
          "angular",
          "angular"
        ],
        [
          "distribution",
          "distribution"
        ],
        [
          "light",
          "light"
        ],
        [
          "reflected",
          "reflected"
        ]
      ],
      "raw_glosses": [
        "(astronomy) A function that describes the angular distribution of light reflected from a body when illuminated from a specific direction"
      ],
      "topics": [
        "astronomy",
        "natural-sciences"
      ]
    }
  ],
  "word": "phase function"
}

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  "lang_code": "en",
  "pos": "noun",
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        "en:Astronomy",
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      ],
      "glosses": [
        "A function that describes the angular distribution of light reflected from a body when illuminated from a specific direction"
      ],
      "links": [
        [
          "astronomy",
          "astronomy"
        ],
        [
          "angular",
          "angular"
        ],
        [
          "distribution",
          "distribution"
        ],
        [
          "light",
          "light"
        ],
        [
          "reflected",
          "reflected"
        ]
      ],
      "raw_glosses": [
        "(astronomy) A function that describes the angular distribution of light reflected from a body when illuminated from a specific direction"
      ],
      "topics": [
        "astronomy",
        "natural-sciences"
      ]
    }
  ],
  "word": "phase function"
}