"first rain" meaning in English

{
  "forms": [
    {
      "form": "first rains",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "first rain (plural first rains)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
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          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w"
        },
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      ],
      "glosses": [
        "The first rainfall of a season, at the start of spring in cold climates or the end of summer in hot, dry climates."
      ],
      "id": "en-first_rain-en-noun-uIdwLYzk",
      "links": [
        [
          "rainfall",
          "rainfall"
        ]
      ],
      "translations": [
        {
          "code": "el",
          "lang": "Greek",
          "roman": "protovróchi",
          "sense": "first rain",
          "tags": [
            "neuter"
          ],
          "word": "πρωτοβρόχι"
        }
      ]
    }
  ],
  "word": "first rain"
}

{
  "forms": [
    {
      "form": "first rains",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "first rain (plural first rains)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "Entries with translation boxes",
        "Pages with 1 entry",
        "Pages with entries",
        "Terms with Greek translations"
      ],
      "glosses": [
        "The first rainfall of a season, at the start of spring in cold climates or the end of summer in hot, dry climates."
      ],
      "links": [
        [
          "rainfall",
          "rainfall"
        ]
      ]
    }
  ],
  "translations": [
    {
      "code": "el",
      "lang": "Greek",
      "roman": "protovróchi",
      "sense": "first rain",
      "tags": [
        "neuter"
      ],
      "word": "πρωτοβρόχι"
    }
  ],
  "word": "first rain"
}