a post bearing a sign that gives directions or shows the way
<noun.communication> [ verb ]
mark with a signpost, as of a path
<verb.communication>
Signpost \Sign"post`\, n. A post on which a sign hangs, or on which papers are placed to give public notice of anything.
Durable goods orders are considered a key signpost for the future since a drop in orders normally triggers cutbacks in production plans and job layoffs.