"not but" meaning in English

{
  "head_templates": [
    {
      "args": {},
      "expansion": "not but",
      "name": "en-conjunction"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "conj",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "1717, Alexander Pope, A Discourse on Pastoral Poetry",
          "text": "Spenser's Calendar, in Mr Dryden's opinion, is the most complete work of this kind which any nation has produced ever since the time of Virgil. Not but that he may be thought imperfect in some few points.",
          "type": "quotation"
        },
        {
          "ref": "1768, Isaac Bickerstaff, Lionel and Clarissa",
          "text": "Not but your father has good qualities, and I assure you I remember him a very fine gentleman himself.",
          "type": "quotation"
        },
        {
          "ref": "1792, Jane Austen, ‘Lesley Castle’, Juvenilia",
          "text": "This was the only very severe thing I ever said in my Life; not but that I have often felt myself extremely satirical but it was the only time I ever made my feelings public.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Introducing a subordinate clause, frequently with that: \"it is not that (the following clause) is not the case\"."
      ],
      "id": "en-not_but-en-conj-s70N9AgB",
      "links": [
        [
          "that",
          "that#English"
        ]
      ],
      "raw_glosses": [
        "(now rare, archaic) Introducing a subordinate clause, frequently with that: \"it is not that (the following clause) is not the case\"."
      ],
      "tags": [
        "archaic"
      ]
    }
  ],
  "word": "not but"
}

{
  "head_templates": [
    {
      "args": {},
      "expansion": "not but",
      "name": "en-conjunction"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "conj",
  "senses": [
    {
      "categories": [
        "English conjunctions",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English terms with archaic senses",
        "English terms with quotations",
        "English terms with rare senses",
        "Quotation templates to be cleaned"
      ],
      "examples": [
        {
          "ref": "1717, Alexander Pope, A Discourse on Pastoral Poetry",
          "text": "Spenser's Calendar, in Mr Dryden's opinion, is the most complete work of this kind which any nation has produced ever since the time of Virgil. Not but that he may be thought imperfect in some few points.",
          "type": "quotation"
        },
        {
          "ref": "1768, Isaac Bickerstaff, Lionel and Clarissa",
          "text": "Not but your father has good qualities, and I assure you I remember him a very fine gentleman himself.",
          "type": "quotation"
        },
        {
          "ref": "1792, Jane Austen, ‘Lesley Castle’, Juvenilia",
          "text": "This was the only very severe thing I ever said in my Life; not but that I have often felt myself extremely satirical but it was the only time I ever made my feelings public.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Introducing a subordinate clause, frequently with that: \"it is not that (the following clause) is not the case\"."
      ],
      "links": [
        [
          "that",
          "that#English"
        ]
      ],
      "raw_glosses": [
        "(now rare, archaic) Introducing a subordinate clause, frequently with that: \"it is not that (the following clause) is not the case\"."
      ],
      "tags": [
        "archaic"
      ]
    }
  ],
  "word": "not but"
}