pole 1 
(pōl)
(pōl)n.
1. Either extremity of an axis through a sphere.
2. Either of the regions contiguous to the extremities of the earth's rotational axis, the North Pole or the South Pole.
3. Physics See magnetic pole.
4. Electricity Either of two oppositely charged terminals, as in an electric cell or battery.
5. Astronomy See celestial pole.
6. Biology
a. Either extremity of the main axis of a nucleus, cell, or organism.
b. Either end of the spindle formed in a cell during mitosis.
c. The point on a nerve cell where a process originates.
7. Either of two antithetical ideas, propensities, forces, or positions.
8. A fixed point of reference.
9. Mathematics
a. The origin in a polar coordinate system; the vertex of a polar angle.
b. A point in the complex plane at which a given function is not defined.
[Middle English, from Old French, from Latin polus, from Greek polos, axis, sky; see kwel-1 in the Appendix of Indo-European roots.]