An Acronym for Top-Level Domain.
.nz is a TLD. So is .com, .net, .museum, .uk etc.
A ccTLD is a country code top level domain such as .nz, .uk, .tv, etc -- always 2 characters. The IANA maintains the official list of ccTLD's.
See DNS.
CategoryDns
4 pages link to TLD:
the official list of ccTLD's.
