exertion

noun

1. use of physical or mental energy; hard work

   noun.act

   Examples

   They managed only with great exertion.

   Synonyms effort elbow grease sweat travail

   Source: WordNet 3.0

2. The act of exerting, or putting into motion or action; the active exercise of any power or faculty; an effort, esp. a laborious or perceptible effort; as, an <i>exertion</i> of strength or power; an <i>exertion</i> of the limbs or of the mind; it is an <i>exertion</i> for him to move, to-day.

   noun

   Source: webster1913