"thre-" meaning in English

{
  "etymology_text": "From threose, formed by changing the letters from the earlier discovered isomer erythrose.",
  "head_templates": [
    {
      "args": {
        "1": "en",
        "2": "prefix"
      },
      "expansion": "thre-",
      "name": "head"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "prefix",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "derived": [
        {
          "word": "threitol"
        },
        {
          "word": "threonate"
        },
        {
          "word": "threonic acid"
        },
        {
          "word": "threonin"
        },
        {
          "word": "threonine"
        },
        {
          "word": "threonyl"
        },
        {
          "word": "threose"
        }
      ],
      "glosses": [
        "Pertaining to general organic structures with adjacent chiral centers"
      ],
      "id": "en-thre--en-prefix-svum2Npd",
      "synonyms": [
        {
          "word": "threo-"
        }
      ],
      "tags": [
        "morpheme"
      ]
    }
  ],
  "word": "thre-"
}

{
  "derived": [
    {
      "word": "threitol"
    },
    {
      "word": "threonate"
    },
    {
      "word": "threonic acid"
    },
    {
      "word": "threonin"
    },
    {
      "word": "threonine"
    },
    {
      "word": "threonyl"
    },
    {
      "word": "threose"
    }
  ],
  "etymology_text": "From threose, formed by changing the letters from the earlier discovered isomer erythrose.",
  "head_templates": [
    {
      "args": {
        "1": "en",
        "2": "prefix"
      },
      "expansion": "thre-",
      "name": "head"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "prefix",
  "senses": [
    {
      "categories": [
        "English entries with incorrect language header",
        "English lemmas",
        "English prefixes"
      ],
      "glosses": [
        "Pertaining to general organic structures with adjacent chiral centers"
      ],
      "tags": [
        "morpheme"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "threo-"
    }
  ],
  "word": "thre-"
}