"in cassum" meaning in Latin

{
  "etymology_templates": [
    {
      "args": {
        "1": "la",
        "2": "in",
        "3": "cassum",
        "t1": "in",
        "t2": "hollow, empty"
      },
      "expansion": "in (“in”) + cassum (“hollow, empty”)",
      "name": "affix"
    },
    {
      "args": {
        "1": "la",
        "2": "cassus"
      },
      "expansion": "cassus",
      "name": "m"
    }
  ],
  "etymology_text": "From in (“in”) + cassum (“hollow, empty”), accusative of cassus.",
  "head_templates": [
    {
      "args": {
        "1": "in cassum",
        "2": "-"
      },
      "expansion": "in cassum (not comparable)",
      "name": "la-adv"
    }
  ],
  "lang": "Latin",
  "lang_code": "la",
  "pos": "adv",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Latin entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "english": "All your promises are in vain.",
          "text": "In cassum cadunt omnia tua promissa.",
          "type": "example"
        },
        {
          "english": "You promise many things to many people: they all prove to be in vain.\nYou pile up fine promises sky-high: down they all drop to nothing. (translated by Paul Nixon, Plautus IV (Loeb), 1980, p. 37)",
          "ref": "c. 194 BCE, Plautus, Poenulus 360",
          "text": "Bene promittis multa ex multis: omnia in cassum cadunt."
        },
        {
          "english": "The prayers were sent in vain.",
          "ref": "27 BCE – 25 BCE, Titus Livius, Ab Urbe Condita 2.49",
          "text": "In cassum missae preces."
        }
      ],
      "glosses": [
        "in vain"
      ],
      "id": "en-in_cassum-la-adv-LseFQXGK",
      "links": [
        [
          "in vain",
          "in vain"
        ]
      ],
      "synonyms": [
        {
          "word": "incassum"
        }
      ],
      "tags": [
        "not-comparable"
      ]
    }
  ],
  "word": "in cassum"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "la",
        "2": "in",
        "3": "cassum",
        "t1": "in",
        "t2": "hollow, empty"
      },
      "expansion": "in (“in”) + cassum (“hollow, empty”)",
      "name": "affix"
    },
    {
      "args": {
        "1": "la",
        "2": "cassus"
      },
      "expansion": "cassus",
      "name": "m"
    }
  ],
  "etymology_text": "From in (“in”) + cassum (“hollow, empty”), accusative of cassus.",
  "head_templates": [
    {
      "args": {
        "1": "in cassum",
        "2": "-"
      },
      "expansion": "in cassum (not comparable)",
      "name": "la-adv"
    }
  ],
  "lang": "Latin",
  "lang_code": "la",
  "pos": "adv",
  "senses": [
    {
      "categories": [
        "Latin adverbs",
        "Latin compound terms",
        "Latin entries with incorrect language header",
        "Latin lemmas",
        "Latin multiword terms",
        "Latin terms with quotations",
        "Latin terms with usage examples",
        "Latin uncomparable adverbs"
      ],
      "examples": [
        {
          "english": "All your promises are in vain.",
          "text": "In cassum cadunt omnia tua promissa.",
          "type": "example"
        },
        {
          "english": "You promise many things to many people: they all prove to be in vain.\nYou pile up fine promises sky-high: down they all drop to nothing. (translated by Paul Nixon, Plautus IV (Loeb), 1980, p. 37)",
          "ref": "c. 194 BCE, Plautus, Poenulus 360",
          "text": "Bene promittis multa ex multis: omnia in cassum cadunt."
        },
        {
          "english": "The prayers were sent in vain.",
          "ref": "27 BCE – 25 BCE, Titus Livius, Ab Urbe Condita 2.49",
          "text": "In cassum missae preces."
        }
      ],
      "glosses": [
        "in vain"
      ],
      "links": [
        [
          "in vain",
          "in vain"
        ]
      ],
      "tags": [
        "not-comparable"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "incassum"
    }
  ],
  "word": "in cassum"
}