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REFERENCE

companion

n.
US //kəmˈpænjən// UK //kəmpˈæniən// com·pan·ion
  1. 1 a friend or partner (n.)
    B2 Upper Intermediate

    a person or animal that you spend time with or travel with.

    a person or animal with whom one spends a significant amount of time or travels. Often implies a relationship based on mutual company rather than just shared tasks.

    Example

    The old man and his dog were constant companions on his morning walks.

    Example

    Finding a reliable travelling companion can be difficult, as long journeys often test even the strongest of friendships.
  2. 2 a matching object (n.)
    C1 Advanced Formal

    one of a pair of things that are meant to be used together.

    one of a pair of things intended to be used together or to complement each other.

    Example

    This book is a companion to the television series and explains the history of the show.

    Example

    The volume was designed as a companion to his earlier work on Renaissance architecture, providing the necessary technical diagrams to support his theories.
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  1. 3 astronomy (n.)
    C2 Proficiency Technical Science

    a star or planet that travels through space with another one.

    a celestial object, such as a star or planet, that is gravitationally bound to or associated with another.

    Example

    The bright star has a small companion that is hard to see without a telescope.

    Example

    Observations of the primary star's wobble suggested the presence of a low-mass companion orbiting at a significant distance.
  2. 4 nautical (n.)
    C2 Proficiency Technical

    the stairs or the cover for the stairs on a ship.

    the covering or framework over a hatchway on a ship's deck, or the ladder leading below.

    Example

    The sailor hurried down the companion to reach the cabin before the storm hit.

    Example

    Water began to seep through the companion as the waves crashed over the quarterdeck, forcing the crew to secure the hatches.
    • hatchway
    • companionway
Origin

From Middle English companion, from Old French compaignon (“companion”) (modern French compagnon), from Late Latin compāniōn- (nominative singular compāniō, whence French copain), from com- + pānis (literally, with + bread), a word first attested in the Frankish Lex Salica as a calque of a Germanic word, probably Frankish galaibo, gahlaibō (“messmate”, literally “with-bread”), from Proto-Germanic *gahlaibô. Compare also Old High German galeipo (“messmate”) and Gothic 𐌲𐌰𐌷𐌻𐌰𐌹𐌱𐌰 (gahlaiba, “messmate”); and, for the semantics, compare Old Armenian ընկեր (ənker, “friend”, literally “messmate”). More at co-, loaf. Displaced native Old English ġefēra (literally “fellow traveler”). Compare company and mate.

Word family

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