hierarchical adj.

"one who rules in holy things," 1570s, from Medieval Latin hierarcha, from Greek hierarkhia, from hierarkhes "leader of sacred rites, high priest" (see hierarchy).

compound adjectival word-forming element, usually interchangeable with -ic but sometimes with specialized sense (such as historic/historical, politic/political), Middle English, from Late Latin -icalis, from Latin -icus + -alis (see -al (1)). Probably it was needed because the forms in -ic often took on a noun sense (for example physic). Forms in -ical tend to be attested earlier in English than their twins in -ic.