expression
despite being busy; without minding the trouble
A formal, somewhat literary set phrase used when someone takes time or makes an effort despite a busy schedule. Often used in expressions of gratitude or admiration.
忙を厭わずご出席いただき、ありがとうございます。
Thank you for attending despite your busy schedule.
彼は忙を厭わず、後輩の指導に当たっている。
He takes time out of his busy schedule to mentor his juniors.