Amiss and Astray share the meaning wrong or otherwise than intended.
Amiss implies failure (as of an arrow) to reach the mark aimed at and frequently suggests a shortcoming or defect (as by failure to reach a standard, an expectation, a definite conclusion, or the point of being useful).
- his shafts of wit went amiss
- she seemed unconcerned, as though nothing had happened amiss
- no information came amiss to him
Sometimes amiss suggests a divergence from the normal or usual order.
- whether his general health had been previously at all amiss
—Dickens - “What’s amiss in the Square?” . . . “Just now I saw a man running along Wedge wood Street”
—Bennett
Astray emphasizes wandering from a predetermined path or the right way or course; it usually suggests moral or intellectual errancy.
- lest in temptation’s path ye gang astray
—Burns - in many an hour when judgment goes astray
—Wordsworth