"low-grade" meaning in English

{
  "antonyms": [
    {
      "word": "high-grade"
    }
  ],
  "forms": [
    {
      "form": "more low-grade",
      "tags": [
        "comparative"
      ]
    },
    {
      "form": "most low-grade",
      "tags": [
        "superlative"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "low-grade (comparative more low-grade, superlative most low-grade)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "derived": [
        {
          "word": "low-grade fever"
        }
      ],
      "examples": [
        {
          "ref": "1961 September, “Talking of Trains: Greater scope for steam”, in Modern Railways, page 517",
          "text": "Were the possibilities of improving the efficiency of British Railways' steam locomotives by making the best use of the reasonably satisfactory low-grade lump coal available today, and thereby saving more high-grade locomotive coal, borne in mind when it was decided to go ahead rapidly with replacement of steam traction?",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Of inferior quality."
      ],
      "id": "en-low-grade-en-adj-DEzwd6jc",
      "links": [
        [
          "inferior",
          "inferior"
        ]
      ],
      "translations": [
        {
          "code": "bg",
          "lang": "Bulgarian",
          "roman": "dolnokačestven",
          "sense": "of inferior quality",
          "word": "долнокачествен"
        },
        {
          "code": "de",
          "lang": "German",
          "sense": "of inferior quality",
          "word": "minderwertig"
        },
        {
          "code": "ml",
          "lang": "Malayalam",
          "roman": "tarantāḻnna",
          "sense": "of inferior quality",
          "word": "തരംതാഴ്ന്ന"
        },
        {
          "code": "ru",
          "lang": "Russian",
          "roman": "nizkosórtnyj",
          "sense": "of inferior quality",
          "word": "низкосо́ртный"
        },
        {
          "code": "ru",
          "lang": "Russian",
          "roman": "nizkopróbnyj",
          "sense": "of inferior quality",
          "word": "низкопро́бный"
        }
      ]
    }
  ],
  "word": "low-grade"
}

{
  "antonyms": [
    {
      "word": "high-grade"
    }
  ],
  "derived": [
    {
      "word": "low-grade fever"
    }
  ],
  "forms": [
    {
      "form": "more low-grade",
      "tags": [
        "comparative"
      ]
    },
    {
      "form": "most low-grade",
      "tags": [
        "superlative"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "low-grade (comparative more low-grade, superlative most low-grade)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        "English adjectives",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English terms with quotations"
      ],
      "examples": [
        {
          "ref": "1961 September, “Talking of Trains: Greater scope for steam”, in Modern Railways, page 517",
          "text": "Were the possibilities of improving the efficiency of British Railways' steam locomotives by making the best use of the reasonably satisfactory low-grade lump coal available today, and thereby saving more high-grade locomotive coal, borne in mind when it was decided to go ahead rapidly with replacement of steam traction?",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Of inferior quality."
      ],
      "links": [
        [
          "inferior",
          "inferior"
        ]
      ]
    }
  ],
  "translations": [
    {
      "code": "bg",
      "lang": "Bulgarian",
      "roman": "dolnokačestven",
      "sense": "of inferior quality",
      "word": "долнокачествен"
    },
    {
      "code": "de",
      "lang": "German",
      "sense": "of inferior quality",
      "word": "minderwertig"
    },
    {
      "code": "ml",
      "lang": "Malayalam",
      "roman": "tarantāḻnna",
      "sense": "of inferior quality",
      "word": "തരംതാഴ്ന്ന"
    },
    {
      "code": "ru",
      "lang": "Russian",
      "roman": "nizkosórtnyj",
      "sense": "of inferior quality",
      "word": "низкосо́ртный"
    },
    {
      "code": "ru",
      "lang": "Russian",
      "roman": "nizkopróbnyj",
      "sense": "of inferior quality",
      "word": "низкопро́бный"
    }
  ],
  "word": "low-grade"
}