The work involved in performing an activity; exertion.
It took a lot of effort to find a decent-sized, fully-furnished apartment within walking distance of the office. He made a conscious effort to not appear affected by the stories in the paper.
An endeavour.
Although he didn't win any medals, Johnson's effort at the Olympics won over many fans.
A force acting on a body in the direction of its motion.
To make an effort.
To strengthen, fortify or stimulate