expression
undaunted by; in defiance of; ignoring
Used in the pattern ...をものともせず（に） to describe acting without being deterred by difficulty, danger, or opposition. Often found in formal or literary contexts.
彼は困難をものともせずに前進した。
He pushed forward undaunted by the difficulties.
選手はけがをものともせず試合に出た。
The athlete played in the match in defiance of the injury.