Source : Webster's Revised Unabridged Dictionary (1913)

Chief \Chief\ (ch[=e]n), n. [OE. chief, chef, OF. chief, F.
   chef, fr. L. caput head, possibly akin to E. head. Cf.
   {Captain}, {Chapter}]
   1. The head or leader of any body of men; a commander, as of
      an army; a head man, as of a tribe, clan, or family; a
      person in authority who directs the work of others; the
      principal actor or agent.

   2. The principal part; the most valuable portion.

            The chief of the things which should be utterly
            destroyed.                            --1 Sam. xv.
                                                  21

   3. (Her.) The upper third part of the field. It is supposed
      to be composed of the dexter, sinister, and middle chiefs.

   {In chief}.
      (a) At the head; as, a commander in chief.
      (b) (Eng. Law) From the king, or sovereign; as, tenure in
          chief, tenure directly from the king.

   Syn: Chieftain; captain; general; commander; leader; head;
        principal; sachem; sagamore; sheik.

   Usage: {Chief}, {chieftain}, {Commander}, {Leader}. These
          words fluctuate somewhat in their meaning according to
          circumstances, but agree in the general idea of rule
          and authority. The term chief is now more usually
          applied to one who is a head man, leader, or commander
          in civil or military affairs, or holds a hereditary or
          acquired rank in a tribe or clan; as, the chief of
          police; the chief of an Indian tribe. A chieftain is
          the chief of a clan or tribe, or a military leader. A
          commander directs the movements of or has control over
          a body of men, as a military or naval force. A leader
          is one whom men follow, as in a political party, a
          legislative body, a military or scientific expedition,
          etc., one who takes the command and gives direction in
          particular enterprises.

Chief \Chief\, a.
   1. Highest in office or rank; principal; head. ``Chief
      rulers.'' --John. xii. 42.

   2. Principal or most eminent in any quality or action; most
      distinguished; having most influence; taking the lead;
      most important; as, the chief topic of conversation; the
      chief interest of man.

   3. Very intimate, near, or close. [Obs.]

            A whisperer separateth chief friends. --Prov. xvi.
                                                  28.

   Syn: Principal; head; leading; main; paramount; supreme;
        prime; vital; especial; great; grand; eminent; master.

Source : WordNet®

chief
     n 1: a person who is in charge; "the head of the whole operation"
          [syn: {head}, {top dog}]
     2: a person who exercises control over workers; "if you want to
        leave early you have to ask the foreman" [syn: {foreman},
        {gaffer}, {honcho}, {boss}]

chief
     adj : most important element; "the chief aim of living"; "the main
           doors were of solid glass"; "the principal rivers of
           America"; "the principal example"; "policemen were
           primary targets" [syn: {chief(a)}, {main(a)}, {primary(a)},
            {principal(a)}]