Both Uses

resignation
in
Murder On The Orient Express
(Edited)

A very distinguished officer had committed suicide, another had suddenly resigned,
Chpt 1.1 *

resigned = quit (from a job or position)
"Well, nothing in the world would surprise me now," said Mr. Hardman with quiet resignation.
Chpt 3.8 *

resignation = having accepted something undesired as unavoidable or the lesser of evils

Definitions:

(1) (resignation as in: submitted her resignation)
to quit -- especially a job or position; or a document expressing such an act
(2) (resignation as in: accepted it with resignation)
acceptance of something undesired as unavoidable or the lesser of evils
(3) (meaning too rare to warrant focus)
To resign can also more specifically mean to surrender or give up as in "I was clearly going to lose the chess game, so I resigned;" or "She resigned all pretense."