"chief rent" meaning in English

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "chief",
        "3": "rent"
      },
      "expansion": "chief + rent",
      "name": "com"
    }
  ],
  "etymology_text": "chief + rent",
  "forms": [
    {
      "form": "chief rents",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "chief rent (plural chief rents)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "British English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "An annual charge on certain freehold properties in England."
      ],
      "id": "en-chief_rent-en-noun-NvPBttlz",
      "links": [
        [
          "freehold",
          "freehold"
        ]
      ],
      "raw_glosses": [
        "(British) An annual charge on certain freehold properties in England."
      ],
      "synonyms": [
        {
          "word": "rentcharge"
        }
      ],
      "tags": [
        "British"
      ]
    }
  ],
  "word": "chief rent"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "chief",
        "3": "rent"
      },
      "expansion": "chief + rent",
      "name": "com"
    }
  ],
  "etymology_text": "chief + rent",
  "forms": [
    {
      "form": "chief rents",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "chief rent (plural chief rents)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "British English",
        "English compound terms",
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns"
      ],
      "glosses": [
        "An annual charge on certain freehold properties in England."
      ],
      "links": [
        [
          "freehold",
          "freehold"
        ]
      ],
      "raw_glosses": [
        "(British) An annual charge on certain freehold properties in England."
      ],
      "tags": [
        "British"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "rentcharge"
    }
  ],
  "word": "chief rent"
}