IMHO, "canonical" has nothing to do with concatenation. What are "canonical" domain names"?subdomain.domain.com is a canonical domain name (I guess it's "in the same canon" as domain.com, as I wrote previously).But this is just a subdomain, isn't it?
Yep but the complete name is often called a canonical name. Probably by the same people who insist on calling abbreviations 'acronyms'.
(In fact, not even TLA is an acronym). :P Maurits.