资料来源 : Webster's Revised Unabridged Dictionary (1913)

Extract \Ex*tract"\, v. t. [imp. & p. p. {Extracted}; p. pr. &
   vb. n. {Extracting}.] [L. extractus, p. p. of extrahere to
   extract; ex out + trahere to draw. See {Trace}, and cf.
   {Estreat}.]
   1. To draw out or forth; to pull out; to remove forcibly from
      a fixed position, as by traction or suction, etc.; as, to
      extract a tooth from its socket, a stump from the earth, a
      splinter from the finger.

            The bee Sits on the bloom extracting liquid sweet.
                                                  --Milton.

   2. To withdraw by expression, distillation, or other
      mechanical or chemical process; as, to extract an essence.
      Cf. {Abstract}, v. t., 6.

            Sunbeams may be extracted from cucumbers, but the
            process is tedious.

   3. To take by selection; to choose out; to cite or quote, as
      a passage from a book.

            I have extracted out of that pamphlet a few
            notorious falsehoods.                 --Swift.

   {To extract the root} (Math.), to ascertain the root of a
      number or quantity.