The Collaborative International Dictionary of English v.0.48:

follow-up \follow-up\ n.
   1. a second (or subsequent) action to increase the
      effectiveness of an initial action. Also used
      attributively; as a follow-up visit.

   Note: A follow-up may be of various types. After a medical
         examination, a second examination (or reexamination)
         to obtain additional information regarding some fact
         discovered in the first examination is considered a
         follow-up. A second visit or phone call in pursuit of a
         sale or other request would also be a follow-up.

   Syn: reexamination, review.
        [WordNet 1.5 +PJC]

   2. (Journalism) A subsequent story providing information
      discovered or events happening after a first story was
      published.
      [PJC]

   3. (Journalism) Same as sidebar.
      [PJC]

The Collaborative International Dictionary of English v.0.48:

Reexamination \Re`ex*am`i*na"tion\ (-?*n?"sh?n), n.
   A repeated examination. See under Examination.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Examination \Ex*am`i*na"tion\, n. [L. examinatio: cf. F.
   examination.]
   1. The act of examining, or state of being examined; a
      careful search, investigation, or inquiry; scrutiny by
      study or experiment.
      [1913 Webster]

   2. A process prescribed or assigned for testing
      qualification; as, the examination of a student, or of a
      candidate for admission to the bar or the ministry.
      [1913 Webster]

            He neglected the studies, . . . stood low at the
            examinations.                         --Macaulay.
      [1913 Webster]

   Examination in chief, or Direct examination (Law), that
      examination which is made of a witness by a party calling
      him.

   Cross-examination, that made by the opposite party.

   Re["e]xamination, or Re-direct examination, (Law) that
      questioning of a witness at trial made by the party
      calling the witness, after, and upon matters arising out
      of, the cross-examination; also called informally
      re-direct.

   Syn: Search; inquiry; investigation; research; scrutiny;
        inquisition; inspection; exploration.
        [1913 Webster]

WordNet (r) 3.0 (2006):

reexamination
    n 1: (law) questioning of a witness by the party that called the
         witness after that witness has been subject to cross-
         examination [syn: redirect examination, reexamination]
    2: a subsequent examination of a patient for the purpose of
       monitoring earlier treatment [syn: follow-up, followup,
       reexamination, review]

Bouvier's Law Dictionary, Revised 6th Ed (1856):

RE-EXAMINATION. A second examination of a thing. A witness maybe reexamined,
in a trial at law, in the discretion of the court, and this is seldom
refused. In equity, it is a general rule that there can be no reexamination
of a witness, after he has once signed his name to the deposition, and
turned his back upon the commissioner or examiner; the reason of this is
that he may be tampered with or induced to retract or qualify what he has
sworn to. 1 Meriv. 130.