"a-" meaning in Spanish

{
  "etymology_number": 1,
  "etymology_templates": [
    {
      "args": {
        "1": "Inherited"
      },
      "expansion": "Inherited",
      "name": "glossary"
    },
    {
      "args": {
        "1": "es",
        "2": "la",
        "3": "ad-",
        "4": "",
        "5": "",
        "g": "",
        "g2": "",
        "g3": "",
        "id": "",
        "lit": "",
        "nocat": "",
        "pos": "",
        "sc": "",
        "sort": "",
        "tr": "",
        "ts": ""
      },
      "expansion": "Latin ad-",
      "name": "inh"
    },
    {
      "args": {
        "1": "es",
        "2": "la",
        "3": "ad-"
      },
      "expansion": "Inherited from Latin ad-",
      "name": "inh+"
    }
  ],
  "etymology_text": "Inherited from Latin ad-.",
  "head_templates": [
    {
      "args": {
        "1": "es",
        "2": "prefix"
      },
      "expansion": "a-",
      "name": "head"
    }
  ],
  "lang": "Spanish",
  "lang_code": "es",
  "pos": "prefix",
  "senses": [
    {
      "glosses": [
        "forms words, especially verbs, that denote entering a state, making progress toward a goal, or the like"
      ],
      "id": "en-a--es-prefix-7EA6GvDn",
      "related": [
        {
          "word": "en-"
        }
      ],
      "tags": [
        "morpheme"
      ]
    }
  ],
  "word": "a-"
}

{
  "etymology_number": 2,
  "etymology_templates": [
    {
      "args": {
        "1": "es",
        "2": "grc",
        "3": "ἀ-"
      },
      "expansion": "Ancient Greek ἀ- (a-)",
      "name": "der"
    }
  ],
  "etymology_text": "From Ancient Greek ἀ- (a-) (ἀν- (an-) immediately preceding a vowel; generalized from the many Latin borrowings using this prefix.",
  "head_templates": [
    {
      "args": {
        "1": "es",
        "2": "prefix"
      },
      "expansion": "a-",
      "name": "head"
    }
  ],
  "lang": "Spanish",
  "lang_code": "es",
  "pos": "prefix",
  "senses": [
    {
      "categories": [
        {
          "_dis": "24 76",
          "kind": "other",
          "name": "Spanish entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        }
      ],
      "glosses": [
        "a-, non-, -less"
      ],
      "id": "en-a--es-prefix-9oA9tMQa",
      "links": [
        [
          "a-",
          "a-#English"
        ],
        [
          "non-",
          "non-"
        ],
        [
          "-less",
          "-less"
        ]
      ],
      "tags": [
        "morpheme"
      ]
    }
  ],
  "word": "a-"
}

{
  "categories": [
    "Pages with 47 entries",
    "Pages with entries",
    "Spanish entries with incorrect language header",
    "Spanish lemmas",
    "Spanish prefixes",
    "Spanish terms derived from Ancient Greek",
    "Spanish terms derived from Latin",
    "Spanish terms inherited from Latin"
  ],
  "etymology_number": 1,
  "etymology_templates": [
    {
      "args": {
        "1": "Inherited"
      },
      "expansion": "Inherited",
      "name": "glossary"
    },
    {
      "args": {
        "1": "es",
        "2": "la",
        "3": "ad-",
        "4": "",
        "5": "",
        "g": "",
        "g2": "",
        "g3": "",
        "id": "",
        "lit": "",
        "nocat": "",
        "pos": "",
        "sc": "",
        "sort": "",
        "tr": "",
        "ts": ""
      },
      "expansion": "Latin ad-",
      "name": "inh"
    },
    {
      "args": {
        "1": "es",
        "2": "la",
        "3": "ad-"
      },
      "expansion": "Inherited from Latin ad-",
      "name": "inh+"
    }
  ],
  "etymology_text": "Inherited from Latin ad-.",
  "head_templates": [
    {
      "args": {
        "1": "es",
        "2": "prefix"
      },
      "expansion": "a-",
      "name": "head"
    }
  ],
  "lang": "Spanish",
  "lang_code": "es",
  "pos": "prefix",
  "related": [
    {
      "word": "en-"
    }
  ],
  "senses": [
    {
      "glosses": [
        "forms words, especially verbs, that denote entering a state, making progress toward a goal, or the like"
      ],
      "tags": [
        "morpheme"
      ]
    }
  ],
  "word": "a-"
}

{
  "categories": [
    "Pages with 47 entries",
    "Pages with entries",
    "Spanish entries with incorrect language header",
    "Spanish lemmas",
    "Spanish prefixes",
    "Spanish terms derived from Ancient Greek"
  ],
  "etymology_number": 2,
  "etymology_templates": [
    {
      "args": {
        "1": "es",
        "2": "grc",
        "3": "ἀ-"
      },
      "expansion": "Ancient Greek ἀ- (a-)",
      "name": "der"
    }
  ],
  "etymology_text": "From Ancient Greek ἀ- (a-) (ἀν- (an-) immediately preceding a vowel; generalized from the many Latin borrowings using this prefix.",
  "head_templates": [
    {
      "args": {
        "1": "es",
        "2": "prefix"
      },
      "expansion": "a-",
      "name": "head"
    }
  ],
  "lang": "Spanish",
  "lang_code": "es",
  "pos": "prefix",
  "senses": [
    {
      "glosses": [
        "a-, non-, -less"
      ],
      "links": [
        [
          "a-",
          "a-#English"
        ],
        [
          "non-",
          "non-"
        ],
        [
          "-less",
          "-less"
        ]
      ],
      "tags": [
        "morpheme"
      ]
    }
  ],
  "word": "a-"
}