Pivot. A pin, spindle or shaft on which a wheel, lever or device rotates or is rotated.
Plane. A level surface, as a table top.
Point. A sharp end. A starting place.
Pores. Minute spaces which separate the molecules of a substance.
Position. The place of a thing when compared to the places of other things.
Precede. To go ahead of. That which is before.
Precession. The act of going ahead or preceding. When a revolving body such as a spinning top or the Earth is acted upon by forces which tend to change the direction of its axis. This change in the direction of its axis is called precessional motion. The pole of the equator of the Earth makes a complete turn round the pole of the ecliptic in a little over 25,000 years and this change in the direction of the axis of the Earth causes the points of the equinox, that is the places where the ecliptic and the equator cross each other to move slowly from west to east and this is termed the precession of the equinoxes.
Prediction. To foretell; to forecast. Predictions may be based on fancy or founded on fact.
Principal. The chief one; the most important.
Principle. The cause of a result. That on which a thing is based.