Source : Webster's Revised Unabridged Dictionary (1913)

Detail \De*tail"\, n. (Arch. & Mach.)
   (a) A minor part, as, in a building, the cornice, caps of the
       buttresses, capitals of the columns, etc., or (called
       {larger details}) a porch, a gable with its windows, a
       pavilion, or an attached tower.
   (b) A detail drawing.

   {In detail}, in subdivisions; part by part; item by item;
      circumstantially; with particularity.

Detail \De"tail\ (d[=e]"t[=a]l or d[-e]*t[=a]l"; 277), n. [F.
   d['e]tail, fr. d['e]tailler to cut in pieces, tell in detail;
   pref. d['e]- (L. de or dis-) + tailler to cut. See {Tailor}.]
   1. A minute portion; one of the small parts; a particular; an
      item; -- used chiefly in the plural; as, the details of a
      scheme or transaction.

            The details of the campaign in Italy. --Motley.

   2. A narrative which relates minute points; an account which
      dwells on particulars.

   3. (Mil.) The selection for a particular service of a person
      or a body of men; hence, the person or the body of men so
      selected.

   {Detail drawing}, a drawing of the full size, or on a large
      scale, of some part of a building, machine, etc.

   {In detail}, in subdivisions; part by part; item;
      circumstantially; with particularity.

   Syn: Account; relation; narrative; recital; explanation;
        narration.

Source : WordNet®

in detail
     adv : thoroughly (including all important particulars); "he
           studied the snake in detail"