"achteran" meaning in Flamand occidental

{
  "categories": [
    {
      "kind": "other",
      "name": "Adverbes en flamand occidental",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Flamand occidental",
      "orig": "flamand occidental",
      "parents": [],
      "source": "w"
    }
  ],
  "lang": "Flamand occidental",
  "lang_code": "vls",
  "pos": "adv",
  "pos_title": "Adverbe",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Flamand français",
          "orig": "flamand français",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "Par derrière, en arrière plan."
      ],
      "id": "fr-achteran-vls-adv-2v1Q6mqG",
      "raw_tags": [
        "Flamand français"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "\\ˈaxtərɑ᷈\\"
    }
  ],
  "word": "achteran"
}

{
  "categories": [
    "Adverbes en flamand occidental",
    "flamand occidental"
  ],
  "lang": "Flamand occidental",
  "lang_code": "vls",
  "pos": "adv",
  "pos_title": "Adverbe",
  "senses": [
    {
      "categories": [
        "flamand français"
      ],
      "glosses": [
        "Par derrière, en arrière plan."
      ],
      "raw_tags": [
        "Flamand français"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "\\ˈaxtərɑ᷈\\"
    }
  ],
  "word": "achteran"
}