Magnetic inclination or Angle of dip: The angle made by the earth's total magnetic field, B with the horizontal direction in the magnetic meridian is called as the magnetic inclination at that place It is the angle by which the total intensity of the earth's magnetic field dips or comes out of the horizontal plane; It is different at different places and measured using a "Dip Circle" 
At the magnetic equator, the dip needle rests horizontally at an angle of zero degrees while, at the magnetic poles, the magnetic needle rests vertically, at an angle of 90 degrees.At all the other places, the angle of dip is between 0 and 90 degrees.