The edge of a road — the strip of ground just beside it where grass and flowers grow. As a plain noun it is old-fashioned; today most people say 'the roadside' or 'the side of the road'. As an adjective before a noun it still turns up in slightly formal or scenic writing: a wayside inn, a wayside shrine, wayside flowers. The word survives mainly because of one very common phrase: **fall by the wayside**. That means to give up, drop out, or be forgotten before the end — the picture is of a traveller who cannot keep walking and sits down at the edge of the road while the others go on. You use it for people who quit a course, for plans that were dropped, for products that stopped selling. 'Of the fifty who started the training, half fell by the wayside.' 'That project fell by the wayside when the budget was cut.' If a student learns only one thing about this word, that phrase is the thing. It is common in newspapers, in meetings, in ordinary speech, and it is where nearly every native speaker's sense of 'wayside' comes from.