"sea-legs" meaning in English

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      "expansion": "sea-legs pl (plural only)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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      "examples": [
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          "ref": "1923, Lucy Maud Montgomery, “Chapter 7”, in Emily of New Moon:",
          "text": "Mary Murray had nearly died of sea-sickness coming out—never seemed to get her sea-legs—so the captain, being sorry for her, told her she could go ashore with the men and feel solid ground under her for an hour or so.",
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      "glosses": [
        "Alternative form of sea legs"
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  "word": "sea-legs"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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      "alt_of": [
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          "word": "sea legs"
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          "ref": "1923, Lucy Maud Montgomery, “Chapter 7”, in Emily of New Moon:",
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  "word": "sea-legs"
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