Difficult, irksome, tedious, boring and unglamorous work or effort needed to achieve success in a business venture, sport or study.

Used in speech as "doing the hard yards" or "putting in the hard yards".

Originated in Australia - New Zealand either in farming or rugby. To create a profitable farm it is necessary to "put in the hard yards" by clearing the land etc. In rugby, to score a try it is necessary for other team members "do the hard yards" by bringing the ball up the field against the opposition's best and brutal efforts so as to create a scoring opportunity