[1] : The Collaborative International Dictionary of English v.0.48

plug \plug\, n. akin to d. plug, g. pflock, dan. pl"ok, plug,
   sw. plugg; cf. w. ploc.
   1. any piece of wood, metal, or other substance used to stop
      or fill a hole; a stopple.
      1913 webster

   2. a flat oblong cake of pressed tobacco. u. s.
      1913 webster

   3. a high, tapering silk hat. slang, u.s.
      1913 webster

   4. a worthless horse. slang, u.s.
      1913 webster

   5. building a block of wood let into a wall, to afford a
      hold for nails.
      1913 webster

   6. an act of plugging6; a brief mention for the sake of
      publicity or advertisement, especially during a public
      event not specifically intended for advertising purposes;
      as, he put in a plug for his favorite charity.
      pjc

   breech plug gun., in breech-loading guns, the metal plug
      or cylinder which closes the aperture in the breech,
      through which the gun is loaded.

   fire plug, a street hydrant to which hose may be attached.
      u. s.

   hawse plug naut., a plug to stop a hawse hole.

   plug and feather. stone working see feather, n., 7.

   plug centerbit, a centerbit ending in a small cylinder
      instead of a point, so as to follow and enlarge a hole
      previously made, or to form a counterbore around it.

   plug rod steam eng., a rod attached to the beam for
      working the valves, as in the cornish engine.

   plug valve mech., a tapering valve, which turns in a case
      like the plug of a faucet.
      1913 webster
see also:
breech plug fire plug hawse plug plug and feather feather plug centerbit 
plug rod plug valve 

Feather >> F Words
Feather, definition of term: Feather
feather_pag1.html

Plug >> P Words
Plug, definition of term: Plug
plug_pag1.html

Plug In >> P Words
Plug In, definition of term: Plug In
plug+in_pag1.html

Plug Hat >> P Words
Plug Hat, definition of term: Plug Hat
plug+hat_pag1.html

Feather Duster >> F Words
Feather Duster, definition of term: Feather Duster
feather+duster_pag1.html

White Feather >> W Words
White Feather, definition of term: White Feather
white+feather_pag1.html

Spark Plug >> S Words
Spark Plug, definition of term: Spark Plug
spark+plug_pag1.html

Plug And Play >> P Words
Plug And Play, definition of term: Plug And Play
plug+and+play_pag1.html

Tar And Feather >> T Words
Tar And Feather, definition of term: Tar And Feather
tar+and+feather_pag1.html