by chance
1. Randomly; without planning or intent. I found a quaint new craft store by chance the other day. I saw your brother by chance yesterday in the grocery store.
2. Perhaps; possibly. Can I get a cup of coffee by chance?
by chance
accidentally; randomly; without planning. I found this book by chance at a book sale. We met by chance in a class in college.
by chance
Casually, accidentally, as in I ran into Bill purely by chance. [c. 1300] Also see by coincidence.
by chance
1. Without plan; accidentally: They met by chance on a plane.
2. Possibly; perchance: Is he, by chance, her brother?