Like hydra neurons

• Like nerve cells with no radiating processes
• Lacking + or -, electrically
• Lacking radiating appendages, as nerve cells
• Electrically balanced, in chemistry
• Having no axes
• Lacking direction, electrically
• Like some nerve cells

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Apolar \A*po"lar\, a. [Pref. a- + polar.] (Biol.) Having no radiating processes; -- applied particularly to certain nerve cells.

Wiktionary Word definitions in Wiktionary
a. 1 Having no polarity 2 # (context chemistry physics English) Having no dipole 3 (context geometry English) Orthogonal under the polar pairing between the symmetric algebra of a vector space and its dual.