what is the difference between architecture and design pattern?

Architecture mostly addresses problems of distributed functionality, system partitioning, protocols, interfaces, scalability, reliability, security and... while design patterns are medium-scale and mostly language-independent abstractions using object oriented mechanisms and described by UML diagrams which solve commonly occurred problems in software construction. 
You might also like to know that Idioms are techniques for expressing low-level and mostly language-dependent ideas for instance inner classes in Java.