In a manner relating to feudalism or feudal principles; according to feudal custom or law.
From feudal plus -ly suffix converting the adjective to an adverb. This adverb allows description of actions, arrangements, or relationships conducted according to feudal norms.
Using 'feudally' in a sentence like 'he feudally owed his lord tribute' sounds archaic now, but it was precise legal language—it indicated you were discussing obligations created by feudal landholding rather than other kinds of debts.
Complete word intelligence in one call. Free tier — 50 lookups/day.