Expedition
An expedition was an excursion, especially a long one, made by a person or a group of people for a specific purpose.

When Spock explained to Captain James T. Kirk about the Eminiar-Vendikar War, Kirk asked if there was anything else, and then Spock answered his question by saying that "The Earth expedition making the report failed to return from its mission. The Valiant. Listed as missing in space." ()

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