"trimestral" meaning in English

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "trimester",
        "3": "al"
      },
      "expansion": "trimester + -al",
      "name": "suffix"
    }
  ],
  "etymology_text": "From trimester + -al.",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "trimestral (not comparable)",
      "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"
        },
        {
          "kind": "other",
          "name": "English terms suffixed with -al",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 5 entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "text": "The school found that a trimestral system mitigated some of the problems caused by its high student turnover.",
          "type": "example"
        }
      ],
      "glosses": [
        "Of trimesters or the use thereof; quarterly; trimonthly."
      ],
      "id": "en-trimestral-en-adj-8u2xDERw",
      "links": [
        [
          "trimester",
          "trimester"
        ]
      ],
      "raw_glosses": [
        "(rare) Of trimesters or the use thereof; quarterly; trimonthly."
      ],
      "tags": [
        "not-comparable",
        "rare"
      ]
    }
  ],
  "word": "trimestral"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "trimester",
        "3": "al"
      },
      "expansion": "trimester + -al",
      "name": "suffix"
    }
  ],
  "etymology_text": "From trimester + -al.",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "trimestral (not comparable)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        "English adjectives",
        "English entries with incorrect language header",
        "English lemmas",
        "English terms suffixed with -al",
        "English terms with rare senses",
        "English terms with usage examples",
        "English uncomparable adjectives",
        "Pages with 5 entries",
        "Pages with entries"
      ],
      "examples": [
        {
          "text": "The school found that a trimestral system mitigated some of the problems caused by its high student turnover.",
          "type": "example"
        }
      ],
      "glosses": [
        "Of trimesters or the use thereof; quarterly; trimonthly."
      ],
      "links": [
        [
          "trimester",
          "trimester"
        ]
      ],
      "raw_glosses": [
        "(rare) Of trimesters or the use thereof; quarterly; trimonthly."
      ],
      "tags": [
        "not-comparable",
        "rare"
      ]
    }
  ],
  "word": "trimestral"
}