The terms 'guide dog' and 'seeing eye dog' can be used interchangeably; they are both common usage.

Essentially they mean the same thing. In Australia we tend to say "guide dog" rather than "seeing eye dog".

A "seeing-eye dog" is a name for a blind person's guide dog. The dog serves as that person's "seeing eye" (i.e., an eye which can see). A guide dog could also be for a person with poor hearing, in this case - the guide dog is not a "seeing-eye dog". A "guide dog" is a dog whose job is to help "guide" its owner during their daily life, especially while walking in public, where there is more danger (for example, crossing the street). 就是說，一個 seeing-eye dog 是一種 guide dog。