fèi​shén

exert effort

费神 (費神) fèi​shén
exert effort adjective
to spend mental energy or take trouble over something

This job is very mentally taxing and requires a great deal of patience.

polite request adjective
a polite expression used when asking someone for a favor or to take care of a matter

I'll have to trouble you, teacher, to look after my child's various daily affairs at school in the future.

Frequency

Movie subtitles
1.10 per million appears in 1% of films
Written text
0.568 per million

Sources

Definitions
CC-CEDICT