Definitions of jar:

• noun:   a vessel (usually cylindrical) with a wide mouth and without handles
• noun:   the quantity contained in a jar

  Example: "He drank a jar of beer"

• noun:   a sudden impact
• verb:   place in a cylindrical vessel

  Example: "Jar the jam"

• verb:   affect in a disagreeable way

  Example: "This play jarred the audience"

• verb:   shock physically
• verb:   be incompatible; be or come into conflict
• verb:   move or cause to move with a sudden jerky motion