The idiomatic expression "to make hay" means to take advantage of a situation or opportunity, often implying that one is working hard or seizing an opportunity while it lasts. The origin of this phrase comes from the traditional process of making hay, which involves cutting grass and allowing it to dry in the sun before storing it for use as animal fodder. During the short period when the grass was dry enough to be cut and gathered, farmers would work long hours to make as much hay as possible while the conditions were right. The phrase has since evolved to mean taking advantage of any opportunity that presents itself, whether in business or personal affairs.