"остръ" meaning in Vieux slave

{
  "categories": [
    {
      "kind": "other",
      "name": "Adjectifs en vieux slave",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Mots en vieux slave issus d’un mot en proto-slave",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Vieux slave",
      "orig": "vieux slave",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Étymologies en vieux slave incluant une reconstruction",
      "parents": [],
      "source": "w"
    }
  ],
  "derived": [
    {
      "word": "острость"
    },
    {
      "lang": "Croate",
      "lang_code": "hr",
      "word": "oštar"
    },
    {
      "lang": "Polonais",
      "lang_code": "pl",
      "word": "ostry"
    },
    {
      "lang": "Tchèque",
      "lang_code": "cs",
      "word": "ostrý"
    }
  ],
  "etymology_texts": [
    "Du proto-slave *ostrъ lui-même issu de l’indo-européen commun *h₂ḱrós ^([1]) (« pointu, aigu ») qui donne acer en latin, âcre en français."
  ],
  "lang": "Vieux slave",
  "lang_code": "cu",
  "pos": "adj",
  "pos_title": "Adjectif",
  "related": [
    {
      "raw_tags": [
        "Glagolitique"
      ],
      "word": "ⰑⰔⰕⰓⰟ"
    }
  ],
  "senses": [
    {
      "glosses": [
        "Aigu, pointu."
      ],
      "id": "fr-остръ-cu-adj-2ZBq0fyx"
    }
  ],
  "word": "остръ"
}

{
  "categories": [
    "Adjectifs en vieux slave",
    "Mots en vieux slave issus d’un mot en proto-slave",
    "vieux slave",
    "Étymologies en vieux slave incluant une reconstruction"
  ],
  "derived": [
    {
      "word": "острость"
    },
    {
      "lang": "Croate",
      "lang_code": "hr",
      "word": "oštar"
    },
    {
      "lang": "Polonais",
      "lang_code": "pl",
      "word": "ostry"
    },
    {
      "lang": "Tchèque",
      "lang_code": "cs",
      "word": "ostrý"
    }
  ],
  "etymology_texts": [
    "Du proto-slave *ostrъ lui-même issu de l’indo-européen commun *h₂ḱrós ^([1]) (« pointu, aigu ») qui donne acer en latin, âcre en français."
  ],
  "lang": "Vieux slave",
  "lang_code": "cu",
  "pos": "adj",
  "pos_title": "Adjectif",
  "related": [
    {
      "raw_tags": [
        "Glagolitique"
      ],
      "word": "ⰑⰔⰕⰓⰟ"
    }
  ],
  "senses": [
    {
      "glosses": [
        "Aigu, pointu."
      ]
    }
  ],
  "word": "остръ"
}