"zero derivation" meaning in English

{
  "forms": [
    {
      "form": "zero derivations",
      "tags": [
        "plural"
      ]
    },
    {
      "form": "zero-derivation",
      "tags": [
        "alternative"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "~"
      },
      "expansion": "zero derivation (countable and uncountable, plural zero derivations)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Entries with translation boxes",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Finnish translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "langcode": "en",
          "name": "Linguistic morphology",
          "orig": "en:Linguistic morphology",
          "parents": [],
          "source": "w"
        }
      ],
      "derived": [
        {
          "word": "zero derive"
        }
      ],
      "glosses": [
        "The derivation of a word from another word (of a differing part of speech) without modification."
      ],
      "id": "en-zero_derivation-en-noun-86~M1ewx",
      "links": [
        [
          "linguistic",
          "linguistic"
        ],
        [
          "morphology",
          "morphology"
        ],
        [
          "derivation",
          "derivation"
        ],
        [
          "part of speech",
          "part of speech"
        ],
        [
          "modification",
          "modification"
        ]
      ],
      "raw_glosses": [
        "(linguistic morphology) The derivation of a word from another word (of a differing part of speech) without modification."
      ],
      "related": [
        {
          "word": "anthimeria"
        }
      ],
      "synonyms": [
        {
          "word": "conversion"
        }
      ],
      "tags": [
        "countable",
        "uncountable"
      ],
      "topics": [
        "human-sciences",
        "linguistic-morphology",
        "linguistics",
        "morphology",
        "sciences"
      ],
      "translations": [
        {
          "code": "fi",
          "lang": "Finnish",
          "lang_code": "fi",
          "sense": "Translations",
          "word": "nollajohto"
        }
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/ˌzɪəɹəʊ ˈdɛɹɪˌveɪʃən/",
      "tags": [
        "UK"
      ]
    },
    {
      "ipa": "/ˌziɹəʊ ˈdɛɹɪˌveɪʃən/",
      "tags": [
        "US"
      ]
    }
  ],
  "word": "zero derivation"
}

{
  "derived": [
    {
      "word": "zero derive"
    }
  ],
  "forms": [
    {
      "form": "zero derivations",
      "tags": [
        "plural"
      ]
    },
    {
      "form": "zero-derivation",
      "tags": [
        "alternative"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "~"
      },
      "expansion": "zero derivation (countable and uncountable, plural zero derivations)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "related": [
    {
      "word": "anthimeria"
    }
  ],
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English uncountable nouns",
        "Entries with translation boxes",
        "Pages with 1 entry",
        "Pages with entries",
        "Terms with Finnish translations",
        "Translation table header lacks gloss",
        "en:Linguistic morphology"
      ],
      "glosses": [
        "The derivation of a word from another word (of a differing part of speech) without modification."
      ],
      "links": [
        [
          "linguistic",
          "linguistic"
        ],
        [
          "morphology",
          "morphology"
        ],
        [
          "derivation",
          "derivation"
        ],
        [
          "part of speech",
          "part of speech"
        ],
        [
          "modification",
          "modification"
        ]
      ],
      "raw_glosses": [
        "(linguistic morphology) The derivation of a word from another word (of a differing part of speech) without modification."
      ],
      "synonyms": [
        {
          "word": "conversion"
        }
      ],
      "tags": [
        "countable",
        "uncountable"
      ],
      "topics": [
        "human-sciences",
        "linguistic-morphology",
        "linguistics",
        "morphology",
        "sciences"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/ˌzɪəɹəʊ ˈdɛɹɪˌveɪʃən/",
      "tags": [
        "UK"
      ]
    },
    {
      "ipa": "/ˌziɹəʊ ˈdɛɹɪˌveɪʃən/",
      "tags": [
        "US"
      ]
    }
  ],
  "translations": [
    {
      "code": "fi",
      "lang": "Finnish",
      "lang_code": "fi",
      "sense": "Translations",
      "word": "nollajohto"
    }
  ],
  "word": "zero derivation"
}