"on serve" meaning in English

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      "expansion": "on serve",
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      "args": {},
      "expansion": "on serve",
      "name": "en-PP"
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  "lang_code": "en",
  "pos": "prep_phrase",
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          "langcode": "en",
          "name": "Tennis",
          "orig": "en:Tennis",
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          "ref": "2010, Caroline Cheese, BBC website:",
          "text": "The fourth set between Gabashvili and Melzer is still on serve, the Russian leading 4-3, but the Austrian holding a two sets to one lead.",
          "type": "quote"
        }
      ],
      "glosses": [
        "With each player or pairing having won the same number of games as they have served."
      ],
      "id": "en-on_serve-en-prep_phrase-tht8TZLW",
      "links": [
        [
          "tennis",
          "tennis"
        ]
      ],
      "raw_glosses": [
        "(tennis) With each player or pairing having won the same number of games as they have served."
      ],
      "topics": [
        "hobbies",
        "lifestyle",
        "sports",
        "tennis"
      ]
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  "word": "on serve"
}

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      "expansion": "on serve",
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          "ref": "2010, Caroline Cheese, BBC website:",
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          "type": "quote"
        }
      ],
      "glosses": [
        "With each player or pairing having won the same number of games as they have served."
      ],
      "links": [
        [
          "tennis",
          "tennis"
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      "raw_glosses": [
        "(tennis) With each player or pairing having won the same number of games as they have served."
      ],
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        "hobbies",
        "lifestyle",
        "sports",
        "tennis"
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  "word": "on serve"
}