一心不乱

いっしんふらん

wholeheartedly; with heart and soul; intently; with undivided attention

Meaning

adj-nan
wholeheartedly; with heart and soul; intently; with undivided attention; with intense concentration; single-mindedly

Example sentences

自分の仕事に一心不乱に打ち込みなさい。

Give yourself to your work with body and soul.
一心不乱に仕事に取り組むのは良いけれど、まわりが全然見えてないね。

It's good to be able to concentrate single-mindedly on your work, but you're completely ignoring the people around you.