heteronomy (n.)

before vowels heter-, word-forming element meaning "other, different," from Greek heteros "the other (of two), another, different; second; other than usual." It is a compound; the first element means "one, at one, together," from PIE root *sem- (1) "one; as one, together with;" the second is cognate with the second element in Latin al-ter, Gothic an-þar, Old English o-ðer "other."

Compounds in classical Greek show the range of the word there: Heterokretes "true Cretan," (that is, of the old stock); heteroglossos "of foreign language;" heterozelos "zealous for one side;" heterotropos "of a different sort or fashion," literally "turning the other way;" heterophron "raving," literally "of other mind."

word-forming element, principally in the science, forming names of disciplines describing natural laws or scientific methods; from Greek -nomia "method," -nomos "managing," nomos "law, usage, custom," all from the verb nemein "to manage," from PIE root *nem- "assign, allot; take." 

Proto-Indo-European root meaning "assign, allot; take."

It forms all or part of: agronomy; anomie; anomy; antinomian; antinomy; astronomer; astronomy; autonomous; autonomy; benumb; Deuteronomy; economy; enumerate; enumeration; gastronomy; heteronomy; innumerable; metronome; namaste; nemesis; nimble; nim; nomad; nomothetic; numb; numeracy; numeral; numerator; numerical; numerology; numerous; numismatic; supernumerary; taxonomy.

It is the hypothetical source of/evidence for its existence is provided by: Greek nemein "to deal out," nemesis "just indignation;" Latin numerus "number;" Lithuanian nuoma "rent, interest;" Middle Irish nos "custom, usage;" German nehmen "to take."