Source : Webster's Revised Unabridged Dictionary (1913)

Preliminary \Pre*lim"i*na*ry\, a. [Pref. pre + L. liminaris
   belonging to a threshold, fr. limen, liminis, threshold,
   entrance: cf. F. pr['e]liminaire. Cf. {Limit}.]
   Introductory; previous; preceding the main discourse or
   business; prefatory; as, preliminary observations to a
   discourse or book; preliminary articles to a treaty;
   preliminary measures; preliminary examinations.

   Syn: Introductory; preparatory; prefatory; proemial;
        previous; prior; precedent; antecedent.

Preliminary \Pre*lim"i*na*ry\, n.; pl. {Preliminaries}.
   That which precedes the main discourse, work, design, or
   business; something introductory or preparatory; as, the
   preliminaries to a negotiation or duel; to take one's
   preliminaries the year before entering college.

   Syn: Introduction; preface; prelude.

Source : WordNet®

preliminary
     adj : designed to orient or acquaint with a situation before
           proceeding; "a preliminary investigation"

preliminary
     n 1: a minor match preceding the main event [syn: {prelim}]
     2: something that serves as a preceding event or introduces
        what follows; "training is a necessary preliminary to
        employment"; "drinks were the overture to dinner" [syn: {overture},
         {prelude}]