noun
one's own rule; personal rule
A self-imposed rule or principle one follows in daily life, often for convenience or personal satisfaction. Wasei-eigo from English 'my rule'.
wasei-eigo (Japanese-coined English), from my rule
私のマイルールは、朝起きたらまず水を一杯飲むことです。
My personal rule is to drink a glass of water first thing in the morning.
彼は仕事中にスマホを見ないというマイルールを決めている。
He has a personal rule not to look at his smartphone during work.