"sulphur rain" meaning in English

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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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          "word": "sulfur rain"
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      "glosses": [
        "Alternative spelling of sulfur rain"
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      "id": "en-sulphur_rain-en-noun-SAENRySH",
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  "word": "sulphur rain"
}

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      "expansion": "sulphur rain",
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "sulfur rain"
        }
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      "glosses": [
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  "word": "sulphur rain"
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