ENGLISH
REFERENCE

tail

n. · v.
US //ˈteɪɫ// UK //tˈeɪl// tail
  1. 1 animal anatomy (n.)
    A1 Beginner

    the part that sticks out from the back of an animal's body.

    the caudal appendage of an animal, typically extending beyond the main torso near the posterior.

    Example

    The dog wagged its tail happily when its owner came home.

    Example

    The lemur uses its long, ringed tail primarily for balance while leaping between the high branches of the rainforest canopy.
  2. 2 back of a vehicle or object (n.)
    B1 Intermediate

    the back or end part of something, like an airplane or a long line.

    the rear structure or terminal part of an object, such as the empennage of an aircraft or the end of a queue.

    Example

    The logo of the airline is painted clearly on the tail of the plane.

    Example

    The investigators focused their search on the tail section of the wreckage, hoping to recover the flight data recorder located in the rear.
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  1. 3 side of a coin (n.)
    B1 Intermediate

    the side of a coin that does not have a person's face on it.

    the reverse side of a coin, typically featuring the denomination rather than a portrait.

    Example

    I flipped a coin and it landed on tails, so I had to wash the dishes.

    Example

    In a fair coin toss, the probability of landing on tails is exactly fifty percent, regardless of previous outcomes.

    Usage

    Usually used in the plural form 'tails' when referring to the side of the coin.
  2. 4 a person following another (n.)
    B2 Upper Intermediate Informal

    someone who is secretly following another person to watch what they do.

    a person, often a private investigator or police officer, assigned to follow and observe a subject surreptitiously.

    Example

    The spy realized he had a tail and tried to get lost in the crowd.

    Example

    The detective suspected that the suspect had spotted his tail, as the man began taking erratic turns through narrow side streets.
  3. 5 comet feature (n.)
    B2 Upper Intermediate Science

    the bright trail of dust and gas that follows a comet in space.

    the visible stream of gas and dust ejected from a comet's nucleus as it approaches the sun.

    Example

    The comet's tail was visible in the night sky for several weeks.

    Example

    A comet's tail always points away from the sun due to the pressure of solar radiation and the solar wind.
  4. 6 body part (n.)
    B2 Upper Intermediate American English Informal

    a person's bottom or backside.

    the human buttocks or posterior region.

    Example

    He fell down on his tail while he was learning how to ice skate.

    Example

    After the long hike, he was happy to finally sit down on his tail and rest by the campfire.
  5. 7 to follow someone (v.)
    B2 Upper Intermediate Informal

    to follow someone closely and secretly to see where they go.

    to follow and observe a person or vehicle surreptitiously, typically for the purpose of surveillance.

    Example

    The police decided to tail the suspect to find out where the money was hidden.

    Example

    Undercover agents were instructed to tail the vehicle from a safe distance to avoid detection while documenting every stop the driver made.

    Usage

    This is a transitive verb and requires a direct object.
Etymology 1

From Middle English tail, tayl, teil, from Old English tæġl (“tail”), from Proto-West Germanic tagl, from Proto-Germanic taglą (“hair, fiber; hair of a tail”), from Proto-Indo-European doḱ- (“hair of the tail”), from Proto-Indo-European deḱ- (“to tear, fray, shred”). Cognate with Scots tail (“tail”), Saterland Frisian Tail (“tail, end”), West Frisian teil (“tail”), Dutch teil (“tail, haulm, blade”), Low German Tagel (“twisted scourge, whip of thongs and ropes; end of a rope”), German Zagel (“tail”), dialectal Danish tavl (“hair of the tail”), Swedish tagel (“hair of the tail, horsehair”), Norwegian tagl (“tail”), Icelandic tagl (“tail, horsetail, ponytail”), Gothic 𐍄𐌰𐌲𐌻 (tagl, “hair”). In some senses, apparently by a generalization of the usual opposition between head and tail.

Etymology 2

From Anglo-Norman, probably from a shortened form of entail.

Word family
Idioms12 entries

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