The adverb therefore means as a result or consequence, or "for that reason." Cats and dogs tend to fight; therefore, keep your pets apart at night if you want to get some sleep.

The adverb therefore is also used to introduce a conclusion that follows based on logic. You'll see this construction a lot in logic, math, and science, for example. Of course, sometimes the conclusions are false, as in this argument: "All fish live in water. A whale lives in water. Therefore, a whale is a fish." A whale is, in fact, a mammal. Therefore, the argument that a whale is a fish is wrong.

Definitions of therefore
  1. adverb
    (used to introduce a logical conclusion) from that fact or reason or as a result
    therefore X must be true”
    synonyms: hence, so, thence, thus
  2. adverb
    as a consequence
    synonyms: consequently
Word Family

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