NECESSITY n. 5 definitions
That which makes an act or an event unavoidable; irresistible force; overruling power; compulsion, physical or moral; fate; fatality. So spake the fiend, and with necessity, The tyrant's plea, excused his devilish deeds. Milton.
OD n.
An alleged force or natural power, supposed, by Reichenbach and others, to produce the phenomena of mesmerism, and to be developed by various agencies, as by magnets, heat, light, chemical or vital action, etc.; -- called also odyle or the odylic force. [Archaic] That od force of German Reichenbach Which still, from fe…