Capacitor
This hieroglyph is often shown composed of three hieroglyphs:
• The positive charge / anode hieroglyph 
• The enclosure hieroglyph 
• The negative charge / cathode hieroglyph 
This hieroglyph therefore represents a capacitor, with the inner negative electrode surrounded by an enclosure, that supports the outer positive electrode.
In the case of the Earth, the ground is the negative electrode, air is the dielectric insulating material that forms the enclosure and the outer positive electrode is the ionosphere.
Because of this, this hieroglyph is often used to describe the Capacitor action of celestial bodies in the Universe.