A replacement is the thing that fills in for something that's missing, or the act of substituting for the missing thing. The replacement for your absent teacher is an annoying substitute. Sigh.

When kids lose their baby teeth, replacements soon grow in their places. And when kids need to have their teeth cleaned but their dentist is on vacation, her replacement will be in charge of taking x-rays and checking for cavities. Replacement comes from the verb replace, which adds the "back" prefix re- to place, "to put somewhere."

Definitions of replacement
  1. noun
    the act of furnishing an equivalent person or thing in the place of another
    synonyms: replacing
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    (law) the replacement of one obligation by another by mutual agreement of both parties; usually the replacement of one of the original parties to a contract with the consent of the remaining party
    pitching change
    replacing a pitcher in baseball
    supersedure, supersession
    act of replacing one person or thing by another especially one held to be superior
    displacement, supplanting
    act of taking the place of another especially using underhanded tactics
    type of:
    commutation, exchange, substitution
    the act of putting one thing or person in the place of another: "he sent Smith in for Jones but the substitution came too late to help"
  2. noun
    an event in which one thing is substituted for another
    “the replacement of lost blood by a transfusion of donor blood”
    synonyms: permutation, substitution, switch, transposition
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    type of:
    fluctuation, variation
    an instance of change; the rate or magnitude of change
  3. noun
    filling again by supplying what has been used up
    synonyms: refilling, renewal, replenishment
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    type of:
    flow into something (as a container)
  4. noun
    someone who takes the place of another person
    synonyms: alternate, surrogate
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    type of:
    backup, backup man, fill-in, relief, reliever, stand-in, substitute
    someone who takes the place of another (as when things get dangerous or difficult)
  5. noun
    a person or thing that takes or can take the place of another
    synonyms: substitute
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    an artificial or inferior substitute or imitation
    a thing or person that immediately replaces something or someone
    (medicine) something that can be used as a substitute (especially any medicine that may be taken in place of another)
    type of:
    a person or thing equal to another in value or measure or force or effect or significance etc
  6. noun
    a person who follows next in order
    synonyms: successor
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    type of:
    compeer, equal, match, peer
    a person who is of equal standing with another in a group
Word Family

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