An Etymological Dictionary of Astronomy and Astrophysics

1. A small hole such as a space especially in a rock, soil, etc. → porous dust grain, → porosity.
   

2. A minute orifice in an animal or plant, as in the skin or a leaf.
   

3. Sun: A small → sunspot that does not have a → penumbra. Pores are up to about 2,500 km across and are lighter than a sunspot’s → umbra. They appear and disappear at the surface of the Sun where sunspots are rarely
   formed, e.g. at low latitudes. Their lifetimes can be as short as 1/2 hour and as long as several days.

Etymology (EN): From L. porus “a pore,” from Gk. poros “a pore,” literally “passage, way,” from PIE root *per- “to lead, pass over.”

Etymology (PE): Lik, from Gilaki lik “hole,” variants luk, luke, liuk, luxa, Tabari luk, li, Sangesari, Semnâni lu, Aftari lo.