"costases" meaning in Spanish

{
  "head_templates": [
    {
      "args": {
        "1": "es",
        "2": "verb form"
      },
      "expansion": "costases",
      "name": "head"
    }
  ],
  "lang": "Spanish",
  "lang_code": "es",
  "pos": "verb",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Spanish entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "form_of": [
        {
          "word": "costar"
        }
      ],
      "glosses": [
        "second-person singular imperfect subjunctive of costar"
      ],
      "id": "en-costases-es-verb-nXEhkSdw",
      "links": [
        [
          "costar",
          "costar#Spanish"
        ]
      ],
      "tags": [
        "form-of",
        "imperfect",
        "second-person",
        "singular",
        "subjunctive"
      ]
    }
  ],
  "word": "costases"
}

{
  "head_templates": [
    {
      "args": {
        "1": "es",
        "2": "verb form"
      },
      "expansion": "costases",
      "name": "head"
    }
  ],
  "lang": "Spanish",
  "lang_code": "es",
  "pos": "verb",
  "senses": [
    {
      "categories": [
        "Pages with 1 entry",
        "Spanish entries with incorrect language header",
        "Spanish non-lemma forms",
        "Spanish verb forms"
      ],
      "form_of": [
        {
          "word": "costar"
        }
      ],
      "glosses": [
        "second-person singular imperfect subjunctive of costar"
      ],
      "links": [
        [
          "costar",
          "costar#Spanish"
        ]
      ],
      "tags": [
        "form-of",
        "imperfect",
        "second-person",
        "singular",
        "subjunctive"
      ]
    }
  ],
  "word": "costases"
}