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REFERENCE

smack

v. · n. · adv.
US //ˈsmæk// UK //smˈæk// smack
  1. 1 to hit (v.)
    B2 Upper Intermediate

    to hit someone or something with the flat part of your hand.

    to strike someone or something with a sharp blow, typically using the palm of the hand.

    Example

    He accidentally smacked his head against the low shelf while standing up.

    Example

    The waves smacked against the side of the wooden pier with surprising force as the storm rolled in from the coast.
  2. 2 a sharp blow (n.)
    B2 Upper Intermediate

    the act or sound of hitting something with your hand.

    a sharp, resounding blow or the specific sound produced by such an impact.

    Example

    We heard the loud smack of the ball hitting the wall.

    Example

    The book fell onto the hardwood floor with a loud smack, startling everyone in the quiet library.
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  1. 3 heroin (n.)
    C2 Proficiency Slang

    a slang name for the illegal drug heroin.

    a slang term for heroin. Uncountable in this sense.

    Example

    The documentary explored the lives of people addicted to smack in the 1970s.

    Example

    Undercover officers were focused on disrupting the local distribution of smack and other Class A substances.
  2. 4 a loud kiss (n.)
    C1 Advanced Informal

    a loud kiss made by pressing the lips together and then opening them quickly.

    a loud, audible kiss, or the sound produced by such a kiss.

    Example

    She gave her grandson a big smack on the cheek.

    Example

    The aunt greeted each of her nephews with a noisy smack on the forehead before ushering them into the house.
  3. 5 exactly or directly (adv.)
    B2 Upper Intermediate Informal

    exactly in a certain place or directly against something.

    directly, squarely, or precisely; often used to describe a physical collision or a specific location.

    Example

    The ball landed smack in the middle of the flower bed.

    Example

    The cyclist rode smack into the back of a parked van because he was looking at his phone.
  4. 6 computing stack (n.)
    C2 Proficiency Technical Computing

    a set of software tools used to handle large amounts of data.

    An acronym for a data processing stack consisting of Spark, Mesos, Akka, Cassandra, and Kafka.

    Example

    The engineering team decided to use the SMACK stack for their new real-time analytics project.

    Example

    Implementing the SMACK stack allowed the company to process millions of events per second with high availability and fault tolerance.

    Usage

    Usually written in all caps as SMACK.

Etymology 1

The noun is from Middle English smac, smak, smacke, from Old English smæc, smæċċ (“taste, smatch”), from Proto-West Germanic smakku, from Proto-Germanic smakkuz (“a taste”), from Proto-Indo-European smegʰ-, smeg- (“to taste”). The verb is from Middle English smaken. Cognate with English dialectal smatch, Scots smak (“scent, smell, taste, flavour”), Saterland Frisian Smoak (“taste”), West Frisian smaak (“taste”), Dutch smaak (“taste”), German Schmack, Geschmack (“taste”), Danish smag (“taste”), Swedish and Norwegian smak (“taste”), Norwegian smekke . Akin to Old English smæċċan (“to taste, smack”). More at smatch.

Etymology 2

From Middle Low German smack (Low German Schmacke, Schmaake (“small ship”)) or Dutch smak, perhaps ultimately related to smakken, imitative of the sails' noise.

Etymology 3

From Middle English smakken, from Middle Dutch smacken (modern Dutch smakken (“to smack, pop, hurl down, crash”)), from Old Dutch smakkon, from Proto-West Germanic *smak(k)ōn, ultimately of imitative origin. Cognate West Frisian smakke, Middle Low German smacken (“to hit, hurl, fling”), Plautdietsch schmaksen (“to smack the lips”), German schmatzen (“eat noisily”), regional German schmacken, Schmackes (“vigour”) (compare Swedish smak (“slap”), the first part of Saterland Frisian smakmuulje (“to smack, slap”)).

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