na-adjective
licentious; self-indulgent; dissolute
Describes a person or behavior that is unrestrained, indulging freely in pleasures, often with a negative moral connotation. Somewhat literary.
彼の放恣な生活は、ついに身を滅ぼした。
His licentious lifestyle eventually ruined him.
放恣な振る舞いは周囲の反感を買う。
Self-indulgent behavior invites resentment from those around you.
The word is composed of 放 (release, let loose) and 恣 (selfish, arbitrary) or 肆 (as one pleases). The exact historical derivation is uncertain, but the combination conveys the idea of acting without restraint.